diff options
| -rw-r--r-- | applets/busybox.c | 9 | ||||
| -rw-r--r-- | busybox.c | 9 | ||||
| -rw-r--r-- | busybox.def.h | 1 | ||||
| -rw-r--r-- | internal.h | 1 | ||||
| -rw-r--r-- | lash.c | 915 | ||||
| -rw-r--r-- | sh.c | 915 | ||||
| -rw-r--r-- | shell/lash.c | 915 | ||||
| -rw-r--r-- | utility.c | 4 |
8 files changed, 2761 insertions, 8 deletions
diff --git a/applets/busybox.c b/applets/busybox.c index cea191cb3..9aa46eaae 100644 --- a/applets/busybox.c +++ b/applets/busybox.c @@ -223,13 +223,16 @@ static const struct Applet applets[] = { #ifdef BB_RMMOD //sbin {"rmmod", rmmod_main}, #endif +#ifdef BB_SED //bin + {"sed", sed_main}, +#endif +#ifdef BB_SH //bin + {"sh", shell_main}, +#endif #ifdef BB_SFDISK //sbin {"fdisk", sfdisk_main}, {"sfdisk", sfdisk_main}, #endif -#ifdef BB_SED //bin - {"sed", sed_main}, -#endif #ifdef BB_SLEEP //bin {"sleep", sleep_main}, #endif @@ -223,13 +223,16 @@ static const struct Applet applets[] = { #ifdef BB_RMMOD //sbin {"rmmod", rmmod_main}, #endif +#ifdef BB_SED //bin + {"sed", sed_main}, +#endif +#ifdef BB_SH //bin + {"sh", shell_main}, +#endif #ifdef BB_SFDISK //sbin {"fdisk", sfdisk_main}, {"sfdisk", sfdisk_main}, #endif -#ifdef BB_SED //bin - {"sed", sed_main}, -#endif #ifdef BB_SLEEP //bin {"sleep", sleep_main}, #endif diff --git a/busybox.def.h b/busybox.def.h index fdbb6fed6..0caa57380 100644 --- a/busybox.def.h +++ b/busybox.def.h @@ -77,6 +77,7 @@ //#define BB_RMMOD #define BB_SED //#define BB_SFDISK +#define BB_SH #define BB_SLEEP #define BB_SORT #define BB_SWAPONOFF diff --git a/internal.h b/internal.h index 2e2556d81..e96eebba9 100644 --- a/internal.h +++ b/internal.h @@ -125,6 +125,7 @@ extern int rmdir_main(int argc, char **argv); extern int rmmod_main(int argc, char** argv); extern int sed_main(int argc, char** argv); extern int sfdisk_main(int argc, char** argv); +extern int shell_main(int argc, char** argv); extern int sleep_main(int argc, char** argv); extern int sort_main(int argc, char** argv); extern int swap_on_off_main(int argc, char** argv); @@ -0,0 +1,915 @@ +/* vi: set sw=4 ts=4: */ +/* + * BusyBox Shell + * + * Copyright (C) 2000 by Lineo, inc. + * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org> + * + * Based in part on ladsh.c by Michael K. Johnson and Erik W. Troan, which is + * under the following liberal license: "We have placed this source code in the + * public domain. Use it in any project, free or commercial." + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include "internal.h" +#include <stdio.h> +#include <stdlib.h> +#include <ctype.h> +#include <errno.h> +#include <fcntl.h> +#include <glob.h> +#include <signal.h> +#include <string.h> +#include <sys/ioctl.h> +#include <sys/wait.h> +#include <unistd.h> + + +#define MAX_COMMAND_LEN 250 /* max length of a single command + string */ +#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n" + +enum redirectionType { REDIRECT_INPUT, REDIRECT_OVERWRITE, REDIRECT_APPEND }; + +struct jobSet { + struct job * head; /* head of list of running jobs */ + struct job * fg; /* current foreground job */ +}; + +struct redirectionSpecifier { + enum redirectionType type; /* type of redirection */ + int fd; /* file descriptor being redirected */ + char * filename; /* file to redirect fd to */ +}; + +struct childProgram { + pid_t pid; /* 0 if exited */ + char ** argv; /* program name and arguments */ + int numRedirections; /* elements in redirection array */ + struct redirectionSpecifier * redirections; /* I/O redirections */ + glob_t globResult; /* result of parameter globbing */ + int freeGlob; /* should we globfree(&globResult)? */ + int isStopped; /* is the program currently running? */ +}; + +struct job { + int jobId; /* job number */ + int numProgs; /* total number of programs in job */ + int runningProgs; /* number of programs running */ + char * text; /* name of job */ + char * cmdBuf; /* buffer various argv's point into */ + pid_t pgrp; /* process group ID for the job */ + struct childProgram * progs; /* array of programs in job */ + struct job * next; /* to track background commands */ + int stoppedProgs; /* number of programs alive, but stopped */ +}; + +struct builtInCommand { + char *cmd; /* name */ + char *descr; /* description */ + char *usage; /* usage */ + int (*function) (struct job *, struct jobSet * jobList); /* function ptr */ +}; + +/* Some function prototypes */ +static int shell_cd(struct job* cmd, struct jobSet* junk); +static int shell_env(struct job* dummy, struct jobSet* junk); +static int shell_exit(struct job* cmd, struct jobSet* junk); +static int shell_fg_bg(struct job* cmd, struct jobSet* jobList); +static int shell_help(struct job* cmd, struct jobSet* junk); +static int shell_jobs(struct job* dummy, struct jobSet* jobList); +static int shell_pwd(struct job* dummy, struct jobSet* junk); +static int shell_set(struct job* cmd, struct jobSet* junk); +static int shell_source(struct job* cmd, struct jobSet* jobList); +static int shell_unset(struct job* cmd, struct jobSet* junk); + +static void checkJobs(struct jobSet * jobList); +static int getCommand(FILE * source, char * command); +static int parseCommand(char ** commandPtr, struct job * job, int * isBg); +static int setupRedirections(struct childProgram * prog); +static int runCommand(struct job newJob, struct jobSet * jobList, int inBg); +static int busy_loop(FILE * input); + + +/* Table of built-in functions */ +static struct builtInCommand bltins[] = { + {"bg", "Resume a job in the background", "bg [%%job]", shell_fg_bg}, + {"cd", "Change working directory", "cd [dir]", shell_cd}, + {"env", "Print all environment variables", "env", shell_env}, + {"exit", "Exit from shell()", "exit", shell_exit}, + {"fg", "Bring job into the foreground", "fg [%%job]", shell_fg_bg}, + {"jobs", "Lists the active jobs", "jobs", shell_jobs}, + {"pwd", "Print current directory", "pwd", shell_pwd}, + {"set", "Set environment variable", "set [VAR=value]", shell_set}, + {"unset", "Unset environment variable", "unset VAR", shell_unset}, + //{"echo", "Echo arguments on stdout", "echo arg1 [...]", shell_echo}, + {".", "Source-in and run commands in a file", ". filename", shell_source}, + {"help", "List shell built-in commands", "help", shell_help}, + {NULL, NULL, NULL, NULL} +}; + +static const char shell_usage[] = + "sh [FILE]...\n\n" + "The BusyBox command interpreter (shell).\n\n"; + + +static char cwd[1024]; +static char *prompt = "# "; + + +/* built-in 'cd <path>' handler */ +static int shell_cd(struct job* cmd, struct jobSet* junk) +{ + char *newdir; + if (!cmd->progs[0].argv[1] == 1) + newdir = getenv("HOME"); + else + newdir = cmd->progs[0].argv[1]; + if (chdir(newdir)) { + printf("cd: %s: %s\n", newdir, strerror(errno)); + return FALSE; + } + getcwd(cwd, sizeof(cwd)); + + return TRUE; +} + +/* built-in 'env' handler */ +static int shell_env(struct job* dummy, struct jobSet* junk) +{ + char **e; + + for (e = environ ; *e ; e++) { + fprintf(stdout, "%s\n", *e); + } + return (0); +} + +/* built-in 'exit' handler */ +static int shell_exit(struct job* cmd, struct jobSet* junk) +{ + if (!cmd->progs[0].argv[1] == 1) + exit TRUE; + else + exit(atoi(cmd->progs[0].argv[1])); +} + +/* built-in 'fg' and 'bg' handler */ +static int shell_fg_bg(struct job* cmd, struct jobSet* jobList) +{ + int i, jobNum; + struct job* job; + + if (!cmd->progs[0].argv[1] || cmd->progs[0].argv[2]) { + fprintf(stderr, "%s: exactly one argument is expected\n", + cmd->progs[0].argv[0]); + return FALSE; + } + + if (sscanf(cmd->progs[0].argv[1], "%%%d", &jobNum) != 1) { + fprintf(stderr, "%s: bad argument '%s'\n", + cmd->progs[0].argv[0], cmd->progs[0].argv[1]); + return FALSE; + } + + for (job = jobList->head; job; job = job->next) + if (job->jobId == jobNum) break; + + if (!job) { + fprintf(stderr, "%s: unknown job %d\n", + cmd->progs[0].argv[0], jobNum); + return FALSE; + } + + if (*cmd->progs[0].argv[0] == 'f') { + /* Make this job the foreground job */ + + if (tcsetpgrp(0, job->pgrp)) + perror("tcsetpgrp"); + jobList->fg = job; + } + + /* Restart the processes in the job */ + for (i = 0; i < job->numProgs; i++) + job->progs[i].isStopped = 0; + + kill(-job->pgrp, SIGCONT); + + job->stoppedProgs = 0; + + return TRUE; +} + +/* built-in 'help' handler */ +static int shell_help(struct job* cmd, struct jobSet* junk) +{ + struct builtInCommand *x; + + fprintf(stdout, "\nBuilt-in commands:\n"); + fprintf(stdout, "-------------------\n"); + for ( x=bltins; x->cmd; x++) { + fprintf(stdout, "%s\t%s\n", x->cmd, x->descr); + } + fprintf(stdout, "\n\n"); + return TRUE; +} + +/* built-in 'jobs' handler */ +static int shell_jobs(struct job* dummy, struct jobSet* jobList) +{ + struct job * job; + char * statusString; + for (job = jobList->head; job; job = job->next) { + if (job->runningProgs == job->stoppedProgs) + statusString = "Stopped"; + else + statusString = "Running"; + + printf(JOB_STATUS_FORMAT, job->jobId, statusString, + job->text); + } + return TRUE; +} + + +/* built-in 'pwd' handler */ +static int shell_pwd(struct job* dummy, struct jobSet* junk) +{ + getcwd(cwd, sizeof(cwd)); + fprintf(stdout, "%s\n", cwd); + return TRUE; +} + +/* built-in 'set VAR=value' handler */ +static int shell_set(struct job* cmd, struct jobSet* junk) +{ + int res; + + if (!cmd->progs[0].argv[1] == 1) { + return (shell_env(cmd, junk)); + } + res = putenv(cmd->progs[0].argv[1]); + if (res) + fprintf(stdout, "set: %s\n", strerror(errno)); + return (res); +} + +/* Built-in '.' handler (read-in and execute commands from file) */ +static int shell_source(struct job* cmd, struct jobSet* junk) +{ + FILE *input; + int status; + + if (!cmd->progs[0].argv[1] == 1) + return FALSE; + + input = fopen(cmd->progs[0].argv[1], "r"); + if (!input) { + fprintf(stdout, "Couldn't open file '%s'\n", cmd->progs[0].argv[1]); + return FALSE; + } + + /* Now run the file */ + status = busy_loop(input); + return (status); +} + +/* built-in 'unset VAR' handler */ +static int shell_unset(struct job* cmd, struct jobSet* junk) +{ + if (!cmd->progs[0].argv[1] == 1) { + fprintf(stdout, "unset: parameter required.\n"); + return FALSE; + } + unsetenv(cmd->progs[0].argv[1]); + return TRUE; +} + +/* free up all memory from a job */ +static void freeJob(struct job * cmd) +{ + int i; + + for (i = 0; i < cmd->numProgs; i++) { + free(cmd->progs[i].argv); + if (cmd->progs[i].redirections) free(cmd->progs[i].redirections); + if (cmd->progs[i].freeGlob) globfree(&cmd->progs[i].globResult); + } + free(cmd->progs); + if (cmd->text) free(cmd->text); + free(cmd->cmdBuf); +} + +/* remove a job from the jobList */ +static void removeJob(struct jobSet * jobList, struct job * job) +{ + struct job * prevJob; + + freeJob(job); + if (job == jobList->head) { + jobList->head = job->next; + } else { + prevJob = jobList->head; + while (prevJob->next != job) prevJob = prevJob->next; + prevJob->next = job->next; + } + + free(job); +} + +/* Checks to see if any background processes have exited -- if they + have, figure out why and see if a job has completed */ +static void checkJobs(struct jobSet * jobList) +{ + struct job * job; + pid_t childpid; + int status; + int progNum=0; + + while ((childpid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) { + for (job = jobList->head; job; job = job->next) { + progNum = 0; + while (progNum < job->numProgs && + job->progs[progNum].pid != childpid) + progNum++; + if (progNum < job->numProgs) break; + } + + if (WIFEXITED(status) || WIFSIGNALED(status)) { + /* child exited */ + job->runningProgs--; + job->progs[progNum].pid = 0; + + if (!job->runningProgs) { + printf(JOB_STATUS_FORMAT, job->jobId, "Done", job->text); + removeJob(jobList, job); + } + } else { + /* child stopped */ + job->stoppedProgs++; + job->progs[progNum].isStopped = 1; + + if (job->stoppedProgs == job->numProgs) { + printf(JOB_STATUS_FORMAT, job->jobId, "Stopped", job->text); + } + } + } + + if (childpid == -1 && errno != ECHILD) + perror("waitpid"); +} + +static int getCommand(FILE * source, char * command) +{ + if (source == stdin) { + fprintf(stdout, "%s %s", cwd, prompt); + fflush(stdout); + } + + if (!fgets(command, MAX_COMMAND_LEN, source)) { + if (source == stdin) printf("\n"); + return 1; + } + + /* remove trailing newline */ + command[strlen(command) - 1] = '\0'; + + return 0; +} + +static void globLastArgument(struct childProgram * prog, int * argcPtr, + int * argcAllocedPtr) +{ + int argc = *argcPtr; + int argcAlloced = *argcAllocedPtr; + int rc; + int flags; + int i; + char * src, * dst; + + if (argc > 1) { /* cmd->globResult is already initialized */ + flags = GLOB_APPEND; + i = prog->globResult.gl_pathc; + } else { + prog->freeGlob = 1; + flags = 0; + i = 0; + } + + rc = glob(prog->argv[argc - 1], flags, NULL, &prog->globResult); + if (rc == GLOB_NOSPACE) { + fprintf(stderr, "out of space during glob operation\n"); + return; + } else if (rc == GLOB_NOMATCH || + (!rc && (prog->globResult.gl_pathc - i) == 1 && + !strcmp(prog->argv[argc - 1], + prog->globResult.gl_pathv[i]))) { + /* we need to remove whatever \ quoting is still present */ + src = dst = prog->argv[argc - 1]; + while (*src) { + if (*src != '\\') *dst++ = *src; + src++; + } + *dst = '\0'; + } else if (!rc) { + argcAlloced += (prog->globResult.gl_pathc - i); + prog->argv = realloc(prog->argv, argcAlloced * sizeof(*prog->argv)); + memcpy(prog->argv + (argc - 1), prog->globResult.gl_pathv + i, + sizeof(*(prog->argv)) * (prog->globResult.gl_pathc - i)); + argc += (prog->globResult.gl_pathc - i - 1); + } + + *argcAllocedPtr = argcAlloced; + *argcPtr = argc; +} + +/* Return cmd->numProgs as 0 if no command is present (e.g. an empty + line). If a valid command is found, commandPtr is set to point to + the beginning of the next command (if the original command had more + then one job associated with it) or NULL if no more commands are + present. */ +static int parseCommand(char ** commandPtr, struct job * job, int * isBg) +{ + char * command; + char * returnCommand = NULL; + char * src, * buf, * chptr; + int argc = 0; + int done = 0; + int argvAlloced; + int i; + char quote = '\0'; + int count; + struct childProgram * prog; + + /* skip leading white space */ + while (**commandPtr && isspace(**commandPtr)) (*commandPtr)++; + + /* this handles empty lines or leading '#' characters */ + if (!**commandPtr || (**commandPtr=='#')) { + job->numProgs = 0; + *commandPtr = NULL; + return 0; + } + + *isBg = 0; + job->numProgs = 1; + job->progs = malloc(sizeof(*job->progs)); + + /* We set the argv elements to point inside of this string. The + memory is freed by freeJob(). + + Getting clean memory relieves us of the task of NULL + terminating things and makes the rest of this look a bit + cleaner (though it is, admittedly, a tad less efficient) */ + job->cmdBuf = command = calloc(1, strlen(*commandPtr) + 1); + job->text = NULL; + + prog = job->progs; + prog->numRedirections = 0; + prog->redirections = NULL; + prog->freeGlob = 0; + prog->isStopped = 0; + + argvAlloced = 5; + prog->argv = malloc(sizeof(*prog->argv) * argvAlloced); + prog->argv[0] = job->cmdBuf; + + buf = command; + src = *commandPtr; + while (*src && !done) { + if (quote == *src) { + quote = '\0'; + } else if (quote) { + if (*src == '\\') { + src++; + if (!*src) { + fprintf(stderr, "character expected after \\\n"); + freeJob(job); + return 1; + } + + /* in shell, "\'" should yield \' */ + if (*src != quote) *buf++ = '\\'; + } else if (*src == '*' || *src == '?' || *src == '[' || + *src == ']') + *buf++ = '\\'; + *buf++ = *src; + } else if (isspace(*src)) { + if (*prog->argv[argc]) { + buf++, argc++; + /* +1 here leaves room for the NULL which ends argv */ + if ((argc + 1) == argvAlloced) { + argvAlloced += 5; + prog->argv = realloc(prog->argv, + sizeof(*prog->argv) * argvAlloced); + } + prog->argv[argc] = buf; + + globLastArgument(prog, &argc, &argvAlloced); + } + } else switch (*src) { + case '"': + case '\'': + quote = *src; + break; + + case '#': /* comment */ + done = 1; + break; + + case '>': /* redirections */ + case '<': + i = prog->numRedirections++; + prog->redirections = realloc(prog->redirections, + sizeof(*prog->redirections) * (i + 1)); + + prog->redirections[i].fd = -1; + if (buf != prog->argv[argc]) { + /* the stuff before this character may be the file number + being redirected */ + prog->redirections[i].fd = strtol(prog->argv[argc], &chptr, 10); + + if (*chptr && *prog->argv[argc]) { + buf++, argc++; + globLastArgument(prog, &argc, &argvAlloced); + } + } + + if (prog->redirections[i].fd == -1) { + if (*src == '>') + prog->redirections[i].fd = 1; + else + prog->redirections[i].fd = 0; + } + + if (*src++ == '>') { + if (*src == '>') + prog->redirections[i].type = REDIRECT_APPEND, src++; + else + prog->redirections[i].type = REDIRECT_OVERWRITE; + } else { + prog->redirections[i].type = REDIRECT_INPUT; + } + + /* This isn't POSIX sh compliant. Oh well. */ + chptr = src; + while (isspace(*chptr)) chptr++; + + if (!*chptr) { + fprintf(stderr, "file name expected after %c\n", *src); + freeJob(job); + return 1; + } + + prog->redirections[i].filename = buf; + while (*chptr && !isspace(*chptr)) + *buf++ = *chptr++; + + src = chptr - 1; /* we src++ later */ + prog->argv[argc] = ++buf; + break; + + case '|': /* pipe */ + /* finish this command */ + if (*prog->argv[argc]) argc++; + if (!argc) { + fprintf(stderr, "empty command in pipe\n"); + freeJob(job); + return 1; + } + prog->argv[argc] = NULL; + + /* and start the next */ + job->numProgs++; + job->progs = realloc(job->progs, + sizeof(*job->progs) * job->numProgs); + prog = job->progs + (job->numProgs - 1); + prog->numRedirections = 0; + prog->redirections = NULL; + prog->freeGlob = 0; + argc = 0; + + argvAlloced = 5; + prog->argv = malloc(sizeof(*prog->argv) * argvAlloced); + prog->argv[0] = ++buf; + + src++; + while (*src && isspace(*src)) src++; + + if (!*src) { + fprintf(stderr, "empty command in pipe\n"); + return 1; + } + src--; /* we'll ++ it at the end of the loop */ + + break; + + case '&': /* background */ + *isBg = 1; + case ';': /* multiple commands */ + done = 1; + returnCommand = *commandPtr + (src - *commandPtr) + 1; + break; + + case '\\': + src++; + if (!*src) { + freeJob(job); + fprintf(stderr, "character expected after \\\n"); + return 1; + } + if (*src == '*' || *src == '[' || *src == ']' || *src == '?') + *buf++ = '\\'; + /* fallthrough */ + default: + *buf++ = *src; + } + + src++; + } + + if (*prog->argv[argc]) { + argc++; + globLastArgument(prog, &argc, &argvAlloced); + } + if (!argc) { + freeJob(job); + return 0; + } + prog->argv[argc] = NULL; + + if (!returnCommand) { + job->text = malloc(strlen(*commandPtr) + 1); + strcpy(job->text, *commandPtr); + } else { + /* This leaves any trailing spaces, which is a bit sloppy */ + + count = returnCommand - *commandPtr; + job->text = malloc(count + 1); + strncpy(job->text, *commandPtr, count); + job->text[count] = '\0'; + } + + *commandPtr = returnCommand; + + return 0; +} + +static int runCommand(struct job newJob, struct jobSet * jobList, + int inBg) +{ + struct job * job; + int i; + int nextin, nextout; + int pipefds[2]; /* pipefd[0] is for reading */ + struct builtInCommand *x; + + /* handle built-ins here -- we don't fork() so we can't background + these very easily */ + for( x=bltins ; x->cmd ; x++) { + if (!strcmp(newJob.progs[0].argv[0], x->cmd)) { + return(x->function(&newJob, jobList)); + } + } + + nextin = 0, nextout = 1; + for (i = 0; i < newJob.numProgs; i++) { + if ((i + 1) < newJob.numProgs) { + pipe(pipefds); + nextout = pipefds[1]; + } else { + nextout = 1; + } + + if (!(newJob.progs[i].pid = fork())) { + signal(SIGTTOU, SIG_DFL); + + if (nextin != 0) { + dup2(nextin, 0); + close(nextin); + } + + if (nextout != 1) { + dup2(nextout, 1); + close(nextout); + } + + /* explicit redirections override pipes */ + setupRedirections(newJob.progs + i); + + execvp(newJob.progs[i].argv[0], newJob.progs[i].argv); + fatalError( "sh: %s: %s\n", newJob.progs[i].argv[0], + strerror(errno)); + } + + /* put our child in the process group whose leader is the + first process in this pipe */ + setpgid(newJob.progs[i].pid, newJob.progs[0].pid); + + if (nextin != 0) close(nextin); + if (nextout != 1) close(nextout); + + /* If there isn't another process, nextin is garbage + but it doesn't matter */ + nextin = pipefds[0]; + } + + newJob.pgrp = newJob.progs[0].pid; + + /* find the ID for the job to use */ + newJob.jobId = 1; + for (job = jobList->head; job; job = job->next) + if (job->jobId >= newJob.jobId) + newJob.jobId = job->jobId + 1; + + /* add the job to the list of running jobs */ + if (!jobList->head) { + job = jobList->head = malloc(sizeof(*job)); + } else { + for (job = jobList->head; job->next; job = job->next); + job->next = malloc(sizeof(*job)); + job = job->next; + } + + *job = newJob; + job->next = NULL; + job->runningProgs = job->numProgs; + job->stoppedProgs = 0; + + if (inBg) { + /* we don't wait for background jobs to return -- append it + to the list of backgrounded jobs and leave it alone */ + + printf("[%d] %d\n", job->jobId, + newJob.progs[newJob.numProgs - 1].pid); + } else { + jobList->fg = job; + + /* move the new process group into the foreground */ + + if (tcsetpgrp(0, newJob.pgrp)) + perror("tcsetpgrp"); + } + + return 0; +} + +static int setupRedirections(struct childProgram * prog) +{ + int i; + int openfd; + int mode=O_RDONLY; + struct redirectionSpecifier * redir = prog->redirections; + + for (i = 0; i < prog->numRedirections; i++, redir++) { + switch (redir->type) { + case REDIRECT_INPUT: + mode = O_RDONLY; + break; + case REDIRECT_OVERWRITE: + mode = O_RDWR | O_CREAT | O_TRUNC; + break; + case REDIRECT_APPEND: + mode = O_RDWR | O_CREAT | O_APPEND; + break; + } + + openfd = open(redir->filename, mode, 0666); + if (openfd < 0) { + /* this could get lost if stderr has been redirected, but + bash and ash both lose it as well (though zsh doesn't!) */ + fprintf(stderr, "error opening %s: %s\n", redir->filename, + strerror(errno)); + return 1; + } + + if (openfd != redir->fd) { + dup2(openfd, redir->fd); + close(openfd); + } + } + + return 0; +} + + +static int busy_loop(FILE * input) +{ + char command[MAX_COMMAND_LEN + 1]; + char * nextCommand = NULL; + struct jobSet jobList = { NULL, NULL }; + struct job newJob; + int i; + int status; + int inBg; + + /* don't pay any attention to this signal; it just confuses + things and isn't really meant for shells anyway */ + signal(SIGTTOU, SIG_IGN); + + while (1) { + if (!jobList.fg) { + /* no job is in the foreground */ + + /* see if any background processes have exited */ + checkJobs(&jobList); + + if (!nextCommand) { + if (getCommand(input, command)) break; + nextCommand = command; + } + + if (!parseCommand(&nextCommand, &newJob, &inBg) && + newJob.numProgs) { + runCommand(newJob, &jobList, inBg); + } + } else { + /* a job is running in the foreground; wait for it */ + i = 0; + while (!jobList.fg->progs[i].pid || + jobList.fg->progs[i].isStopped) i++; + + waitpid(jobList.fg->progs[i].pid, &status, WUNTRACED); + + if (WIFEXITED(status) || WIFSIGNALED(status)) { + /* the child exited */ + jobList.fg->runningProgs--; + jobList.fg->progs[i].pid = 0; + + if (!jobList.fg->runningProgs) { + /* child exited */ + + removeJob(&jobList, jobList.fg); + jobList.fg = NULL; + + /* move the shell to the foreground */ + if (tcsetpgrp(0, getpid())) + perror("tcsetpgrp"); + } + } else { + /* the child was stopped */ + jobList.fg->stoppedProgs++; + jobList.fg->progs[i].isStopped = 1; + + if (jobList.fg->stoppedProgs == jobList.fg->runningProgs) { + printf("\n" JOB_STATUS_FORMAT, jobList.fg->jobId, + "Stopped", jobList.fg->text); + jobList.fg = NULL; + } + } + + if (!jobList.fg) { + /* move the shell to the foreground */ + if (tcsetpgrp(0, getpid())) + perror("tcsetpgrp"); + } + } + } + + return 0; +} + + +int shell_main(int argc, char ** argv) +{ + FILE * input = stdin; + + if (argc > 2) { + usage( shell_usage); + } + /* initialize the cwd */ + getcwd(cwd, sizeof(cwd)); + + + //if (argv[0] && argv[0][0] == '-') { + // shell_source("/etc/profile"); + //} + + if (argc < 2) { + fprintf(stdout, "\n\nBusyBox v%s (%s) Built-in shell\n", BB_VER, BB_BT); + fprintf(stdout, "Enter 'help' for a list of built-in commands.\n\n"); + } else { + input = fopen(argv[1], "r"); + if (!input) + fatalError("A: Couldn't open file '%s': %s\n", argv[1], strerror(errno)); +// else +// fatalError("Got it.\n"); + //exit(shell_source(argv[1])); + } + + return (busy_loop( input)); +} @@ -0,0 +1,915 @@ +/* vi: set sw=4 ts=4: */ +/* + * BusyBox Shell + * + * Copyright (C) 2000 by Lineo, inc. + * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org> + * + * Based in part on ladsh.c by Michael K. Johnson and Erik W. Troan, which is + * under the following liberal license: "We have placed this source code in the + * public domain. Use it in any project, free or commercial." + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include "internal.h" +#include <stdio.h> +#include <stdlib.h> +#include <ctype.h> +#include <errno.h> +#include <fcntl.h> +#include <glob.h> +#include <signal.h> +#include <string.h> +#include <sys/ioctl.h> +#include <sys/wait.h> +#include <unistd.h> + + +#define MAX_COMMAND_LEN 250 /* max length of a single command + string */ +#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n" + +enum redirectionType { REDIRECT_INPUT, REDIRECT_OVERWRITE, REDIRECT_APPEND }; + +struct jobSet { + struct job * head; /* head of list of running jobs */ + struct job * fg; /* current foreground job */ +}; + +struct redirectionSpecifier { + enum redirectionType type; /* type of redirection */ + int fd; /* file descriptor being redirected */ + char * filename; /* file to redirect fd to */ +}; + +struct childProgram { + pid_t pid; /* 0 if exited */ + char ** argv; /* program name and arguments */ + int numRedirections; /* elements in redirection array */ + struct redirectionSpecifier * redirections; /* I/O redirections */ + glob_t globResult; /* result of parameter globbing */ + int freeGlob; /* should we globfree(&globResult)? */ + int isStopped; /* is the program currently running? */ +}; + +struct job { + int jobId; /* job number */ + int numProgs; /* total number of programs in job */ + int runningProgs; /* number of programs running */ + char * text; /* name of job */ + char * cmdBuf; /* buffer various argv's point into */ + pid_t pgrp; /* process group ID for the job */ + struct childProgram * progs; /* array of programs in job */ + struct job * next; /* to track background commands */ + int stoppedProgs; /* number of programs alive, but stopped */ +}; + +struct builtInCommand { + char *cmd; /* name */ + char *descr; /* description */ + char *usage; /* usage */ + int (*function) (struct job *, struct jobSet * jobList); /* function ptr */ +}; + +/* Some function prototypes */ +static int shell_cd(struct job* cmd, struct jobSet* junk); +static int shell_env(struct job* dummy, struct jobSet* junk); +static int shell_exit(struct job* cmd, struct jobSet* junk); +static int shell_fg_bg(struct job* cmd, struct jobSet* jobList); +static int shell_help(struct job* cmd, struct jobSet* junk); +static int shell_jobs(struct job* dummy, struct jobSet* jobList); +static int shell_pwd(struct job* dummy, struct jobSet* junk); +static int shell_set(struct job* cmd, struct jobSet* junk); +static int shell_source(struct job* cmd, struct jobSet* jobList); +static int shell_unset(struct job* cmd, struct jobSet* junk); + +static void checkJobs(struct jobSet * jobList); +static int getCommand(FILE * source, char * command); +static int parseCommand(char ** commandPtr, struct job * job, int * isBg); +static int setupRedirections(struct childProgram * prog); +static int runCommand(struct job newJob, struct jobSet * jobList, int inBg); +static int busy_loop(FILE * input); + + +/* Table of built-in functions */ +static struct builtInCommand bltins[] = { + {"bg", "Resume a job in the background", "bg [%%job]", shell_fg_bg}, + {"cd", "Change working directory", "cd [dir]", shell_cd}, + {"env", "Print all environment variables", "env", shell_env}, + {"exit", "Exit from shell()", "exit", shell_exit}, + {"fg", "Bring job into the foreground", "fg [%%job]", shell_fg_bg}, + {"jobs", "Lists the active jobs", "jobs", shell_jobs}, + {"pwd", "Print current directory", "pwd", shell_pwd}, + {"set", "Set environment variable", "set [VAR=value]", shell_set}, + {"unset", "Unset environment variable", "unset VAR", shell_unset}, + //{"echo", "Echo arguments on stdout", "echo arg1 [...]", shell_echo}, + {".", "Source-in and run commands in a file", ". filename", shell_source}, + {"help", "List shell built-in commands", "help", shell_help}, + {NULL, NULL, NULL, NULL} +}; + +static const char shell_usage[] = + "sh [FILE]...\n\n" + "The BusyBox command interpreter (shell).\n\n"; + + +static char cwd[1024]; +static char *prompt = "# "; + + +/* built-in 'cd <path>' handler */ +static int shell_cd(struct job* cmd, struct jobSet* junk) +{ + char *newdir; + if (!cmd->progs[0].argv[1] == 1) + newdir = getenv("HOME"); + else + newdir = cmd->progs[0].argv[1]; + if (chdir(newdir)) { + printf("cd: %s: %s\n", newdir, strerror(errno)); + return FALSE; + } + getcwd(cwd, sizeof(cwd)); + + return TRUE; +} + +/* built-in 'env' handler */ +static int shell_env(struct job* dummy, struct jobSet* junk) +{ + char **e; + + for (e = environ ; *e ; e++) { + fprintf(stdout, "%s\n", *e); + } + return (0); +} + +/* built-in 'exit' handler */ +static int shell_exit(struct job* cmd, struct jobSet* junk) +{ + if (!cmd->progs[0].argv[1] == 1) + exit TRUE; + else + exit(atoi(cmd->progs[0].argv[1])); +} + +/* built-in 'fg' and 'bg' handler */ +static int shell_fg_bg(struct job* cmd, struct jobSet* jobList) +{ + int i, jobNum; + struct job* job; + + if (!cmd->progs[0].argv[1] || cmd->progs[0].argv[2]) { + fprintf(stderr, "%s: exactly one argument is expected\n", + cmd->progs[0].argv[0]); + return FALSE; + } + + if (sscanf(cmd->progs[0].argv[1], "%%%d", &jobNum) != 1) { + fprintf(stderr, "%s: bad argument '%s'\n", + cmd->progs[0].argv[0], cmd->progs[0].argv[1]); + return FALSE; + } + + for (job = jobList->head; job; job = job->next) + if (job->jobId == jobNum) break; + + if (!job) { + fprintf(stderr, "%s: unknown job %d\n", + cmd->progs[0].argv[0], jobNum); + return FALSE; + } + + if (*cmd->progs[0].argv[0] == 'f') { + /* Make this job the foreground job */ + + if (tcsetpgrp(0, job->pgrp)) + perror("tcsetpgrp"); + jobList->fg = job; + } + + /* Restart the processes in the job */ + for (i = 0; i < job->numProgs; i++) + job->progs[i].isStopped = 0; + + kill(-job->pgrp, SIGCONT); + + job->stoppedProgs = 0; + + return TRUE; +} + +/* built-in 'help' handler */ +static int shell_help(struct job* cmd, struct jobSet* junk) +{ + struct builtInCommand *x; + + fprintf(stdout, "\nBuilt-in commands:\n"); + fprintf(stdout, "-------------------\n"); + for ( x=bltins; x->cmd; x++) { + fprintf(stdout, "%s\t%s\n", x->cmd, x->descr); + } + fprintf(stdout, "\n\n"); + return TRUE; +} + +/* built-in 'jobs' handler */ +static int shell_jobs(struct job* dummy, struct jobSet* jobList) +{ + struct job * job; + char * statusString; + for (job = jobList->head; job; job = job->next) { + if (job->runningProgs == job->stoppedProgs) + statusString = "Stopped"; + else + statusString = "Running"; + + printf(JOB_STATUS_FORMAT, job->jobId, statusString, + job->text); + } + return TRUE; +} + + +/* built-in 'pwd' handler */ +static int shell_pwd(struct job* dummy, struct jobSet* junk) +{ + getcwd(cwd, sizeof(cwd)); + fprintf(stdout, "%s\n", cwd); + return TRUE; +} + +/* built-in 'set VAR=value' handler */ +static int shell_set(struct job* cmd, struct jobSet* junk) +{ + int res; + + if (!cmd->progs[0].argv[1] == 1) { + return (shell_env(cmd, junk)); + } + res = putenv(cmd->progs[0].argv[1]); + if (res) + fprintf(stdout, "set: %s\n", strerror(errno)); + return (res); +} + +/* Built-in '.' handler (read-in and execute commands from file) */ +static int shell_source(struct job* cmd, struct jobSet* junk) +{ + FILE *input; + int status; + + if (!cmd->progs[0].argv[1] == 1) + return FALSE; + + input = fopen(cmd->progs[0].argv[1], "r"); + if (!input) { + fprintf(stdout, "Couldn't open file '%s'\n", cmd->progs[0].argv[1]); + return FALSE; + } + + /* Now run the file */ + status = busy_loop(input); + return (status); +} + +/* built-in 'unset VAR' handler */ +static int shell_unset(struct job* cmd, struct jobSet* junk) +{ + if (!cmd->progs[0].argv[1] == 1) { + fprintf(stdout, "unset: parameter required.\n"); + return FALSE; + } + unsetenv(cmd->progs[0].argv[1]); + return TRUE; +} + +/* free up all memory from a job */ +static void freeJob(struct job * cmd) +{ + int i; + + for (i = 0; i < cmd->numProgs; i++) { + free(cmd->progs[i].argv); + if (cmd->progs[i].redirections) free(cmd->progs[i].redirections); + if (cmd->progs[i].freeGlob) globfree(&cmd->progs[i].globResult); + } + free(cmd->progs); + if (cmd->text) free(cmd->text); + free(cmd->cmdBuf); +} + +/* remove a job from the jobList */ +static void removeJob(struct jobSet * jobList, struct job * job) +{ + struct job * prevJob; + + freeJob(job); + if (job == jobList->head) { + jobList->head = job->next; + } else { + prevJob = jobList->head; + while (prevJob->next != job) prevJob = prevJob->next; + prevJob->next = job->next; + } + + free(job); +} + +/* Checks to see if any background processes have exited -- if they + have, figure out why and see if a job has completed */ +static void checkJobs(struct jobSet * jobList) +{ + struct job * job; + pid_t childpid; + int status; + int progNum=0; + + while ((childpid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) { + for (job = jobList->head; job; job = job->next) { + progNum = 0; + while (progNum < job->numProgs && + job->progs[progNum].pid != childpid) + progNum++; + if (progNum < job->numProgs) break; + } + + if (WIFEXITED(status) || WIFSIGNALED(status)) { + /* child exited */ + job->runningProgs--; + job->progs[progNum].pid = 0; + + if (!job->runningProgs) { + printf(JOB_STATUS_FORMAT, job->jobId, "Done", job->text); + removeJob(jobList, job); + } + } else { + /* child stopped */ + job->stoppedProgs++; + job->progs[progNum].isStopped = 1; + + if (job->stoppedProgs == job->numProgs) { + printf(JOB_STATUS_FORMAT, job->jobId, "Stopped", job->text); + } + } + } + + if (childpid == -1 && errno != ECHILD) + perror("waitpid"); +} + +static int getCommand(FILE * source, char * command) +{ + if (source == stdin) { + fprintf(stdout, "%s %s", cwd, prompt); + fflush(stdout); + } + + if (!fgets(command, MAX_COMMAND_LEN, source)) { + if (source == stdin) printf("\n"); + return 1; + } + + /* remove trailing newline */ + command[strlen(command) - 1] = '\0'; + + return 0; +} + +static void globLastArgument(struct childProgram * prog, int * argcPtr, + int * argcAllocedPtr) +{ + int argc = *argcPtr; + int argcAlloced = *argcAllocedPtr; + int rc; + int flags; + int i; + char * src, * dst; + + if (argc > 1) { /* cmd->globResult is already initialized */ + flags = GLOB_APPEND; + i = prog->globResult.gl_pathc; + } else { + prog->freeGlob = 1; + flags = 0; + i = 0; + } + + rc = glob(prog->argv[argc - 1], flags, NULL, &prog->globResult); + if (rc == GLOB_NOSPACE) { + fprintf(stderr, "out of space during glob operation\n"); + return; + } else if (rc == GLOB_NOMATCH || + (!rc && (prog->globResult.gl_pathc - i) == 1 && + !strcmp(prog->argv[argc - 1], + prog->globResult.gl_pathv[i]))) { + /* we need to remove whatever \ quoting is still present */ + src = dst = prog->argv[argc - 1]; + while (*src) { + if (*src != '\\') *dst++ = *src; + src++; + } + *dst = '\0'; + } else if (!rc) { + argcAlloced += (prog->globResult.gl_pathc - i); + prog->argv = realloc(prog->argv, argcAlloced * sizeof(*prog->argv)); + memcpy(prog->argv + (argc - 1), prog->globResult.gl_pathv + i, + sizeof(*(prog->argv)) * (prog->globResult.gl_pathc - i)); + argc += (prog->globResult.gl_pathc - i - 1); + } + + *argcAllocedPtr = argcAlloced; + *argcPtr = argc; +} + +/* Return cmd->numProgs as 0 if no command is present (e.g. an empty + line). If a valid command is found, commandPtr is set to point to + the beginning of the next command (if the original command had more + then one job associated with it) or NULL if no more commands are + present. */ +static int parseCommand(char ** commandPtr, struct job * job, int * isBg) +{ + char * command; + char * returnCommand = NULL; + char * src, * buf, * chptr; + int argc = 0; + int done = 0; + int argvAlloced; + int i; + char quote = '\0'; + int count; + struct childProgram * prog; + + /* skip leading white space */ + while (**commandPtr && isspace(**commandPtr)) (*commandPtr)++; + + /* this handles empty lines or leading '#' characters */ + if (!**commandPtr || (**commandPtr=='#')) { + job->numProgs = 0; + *commandPtr = NULL; + return 0; + } + + *isBg = 0; + job->numProgs = 1; + job->progs = malloc(sizeof(*job->progs)); + + /* We set the argv elements to point inside of this string. The + memory is freed by freeJob(). + + Getting clean memory relieves us of the task of NULL + terminating things and makes the rest of this look a bit + cleaner (though it is, admittedly, a tad less efficient) */ + job->cmdBuf = command = calloc(1, strlen(*commandPtr) + 1); + job->text = NULL; + + prog = job->progs; + prog->numRedirections = 0; + prog->redirections = NULL; + prog->freeGlob = 0; + prog->isStopped = 0; + + argvAlloced = 5; + prog->argv = malloc(sizeof(*prog->argv) * argvAlloced); + prog->argv[0] = job->cmdBuf; + + buf = command; + src = *commandPtr; + while (*src && !done) { + if (quote == *src) { + quote = '\0'; + } else if (quote) { + if (*src == '\\') { + src++; + if (!*src) { + fprintf(stderr, "character expected after \\\n"); + freeJob(job); + return 1; + } + + /* in shell, "\'" should yield \' */ + if (*src != quote) *buf++ = '\\'; + } else if (*src == '*' || *src == '?' || *src == '[' || + *src == ']') + *buf++ = '\\'; + *buf++ = *src; + } else if (isspace(*src)) { + if (*prog->argv[argc]) { + buf++, argc++; + /* +1 here leaves room for the NULL which ends argv */ + if ((argc + 1) == argvAlloced) { + argvAlloced += 5; + prog->argv = realloc(prog->argv, + sizeof(*prog->argv) * argvAlloced); + } + prog->argv[argc] = buf; + + globLastArgument(prog, &argc, &argvAlloced); + } + } else switch (*src) { + case '"': + case '\'': + quote = *src; + break; + + case '#': /* comment */ + done = 1; + break; + + case '>': /* redirections */ + case '<': + i = prog->numRedirections++; + prog->redirections = realloc(prog->redirections, + sizeof(*prog->redirections) * (i + 1)); + + prog->redirections[i].fd = -1; + if (buf != prog->argv[argc]) { + /* the stuff before this character may be the file number + being redirected */ + prog->redirections[i].fd = strtol(prog->argv[argc], &chptr, 10); + + if (*chptr && *prog->argv[argc]) { + buf++, argc++; + globLastArgument(prog, &argc, &argvAlloced); + } + } + + if (prog->redirections[i].fd == -1) { + if (*src == '>') + prog->redirections[i].fd = 1; + else + prog->redirections[i].fd = 0; + } + + if (*src++ == '>') { + if (*src == '>') + prog->redirections[i].type = REDIRECT_APPEND, src++; + else + prog->redirections[i].type = REDIRECT_OVERWRITE; + } else { + prog->redirections[i].type = REDIRECT_INPUT; + } + + /* This isn't POSIX sh compliant. Oh well. */ + chptr = src; + while (isspace(*chptr)) chptr++; + + if (!*chptr) { + fprintf(stderr, "file name expected after %c\n", *src); + freeJob(job); + return 1; + } + + prog->redirections[i].filename = buf; + while (*chptr && !isspace(*chptr)) + *buf++ = *chptr++; + + src = chptr - 1; /* we src++ later */ + prog->argv[argc] = ++buf; + break; + + case '|': /* pipe */ + /* finish this command */ + if (*prog->argv[argc]) argc++; + if (!argc) { + fprintf(stderr, "empty command in pipe\n"); + freeJob(job); + return 1; + } + prog->argv[argc] = NULL; + + /* and start the next */ + job->numProgs++; + job->progs = realloc(job->progs, + sizeof(*job->progs) * job->numProgs); + prog = job->progs + (job->numProgs - 1); + prog->numRedirections = 0; + prog->redirections = NULL; + prog->freeGlob = 0; + argc = 0; + + argvAlloced = 5; + prog->argv = malloc(sizeof(*prog->argv) * argvAlloced); + prog->argv[0] = ++buf; + + src++; + while (*src && isspace(*src)) src++; + + if (!*src) { + fprintf(stderr, "empty command in pipe\n"); + return 1; + } + src--; /* we'll ++ it at the end of the loop */ + + break; + + case '&': /* background */ + *isBg = 1; + case ';': /* multiple commands */ + done = 1; + returnCommand = *commandPtr + (src - *commandPtr) + 1; + break; + + case '\\': + src++; + if (!*src) { + freeJob(job); + fprintf(stderr, "character expected after \\\n"); + return 1; + } + if (*src == '*' || *src == '[' || *src == ']' || *src == '?') + *buf++ = '\\'; + /* fallthrough */ + default: + *buf++ = *src; + } + + src++; + } + + if (*prog->argv[argc]) { + argc++; + globLastArgument(prog, &argc, &argvAlloced); + } + if (!argc) { + freeJob(job); + return 0; + } + prog->argv[argc] = NULL; + + if (!returnCommand) { + job->text = malloc(strlen(*commandPtr) + 1); + strcpy(job->text, *commandPtr); + } else { + /* This leaves any trailing spaces, which is a bit sloppy */ + + count = returnCommand - *commandPtr; + job->text = malloc(count + 1); + strncpy(job->text, *commandPtr, count); + job->text[count] = '\0'; + } + + *commandPtr = returnCommand; + + return 0; +} + +static int runCommand(struct job newJob, struct jobSet * jobList, + int inBg) +{ + struct job * job; + int i; + int nextin, nextout; + int pipefds[2]; /* pipefd[0] is for reading */ + struct builtInCommand *x; + + /* handle built-ins here -- we don't fork() so we can't background + these very easily */ + for( x=bltins ; x->cmd ; x++) { + if (!strcmp(newJob.progs[0].argv[0], x->cmd)) { + return(x->function(&newJob, jobList)); + } + } + + nextin = 0, nextout = 1; + for (i = 0; i < newJob.numProgs; i++) { + if ((i + 1) < newJob.numProgs) { + pipe(pipefds); + nextout = pipefds[1]; + } else { + nextout = 1; + } + + if (!(newJob.progs[i].pid = fork())) { + signal(SIGTTOU, SIG_DFL); + + if (nextin != 0) { + dup2(nextin, 0); + close(nextin); + } + + if (nextout != 1) { + dup2(nextout, 1); + close(nextout); + } + + /* explicit redirections override pipes */ + setupRedirections(newJob.progs + i); + + execvp(newJob.progs[i].argv[0], newJob.progs[i].argv); + fatalError( "sh: %s: %s\n", newJob.progs[i].argv[0], + strerror(errno)); + } + + /* put our child in the process group whose leader is the + first process in this pipe */ + setpgid(newJob.progs[i].pid, newJob.progs[0].pid); + + if (nextin != 0) close(nextin); + if (nextout != 1) close(nextout); + + /* If there isn't another process, nextin is garbage + but it doesn't matter */ + nextin = pipefds[0]; + } + + newJob.pgrp = newJob.progs[0].pid; + + /* find the ID for the job to use */ + newJob.jobId = 1; + for (job = jobList->head; job; job = job->next) + if (job->jobId >= newJob.jobId) + newJob.jobId = job->jobId + 1; + + /* add the job to the list of running jobs */ + if (!jobList->head) { + job = jobList->head = malloc(sizeof(*job)); + } else { + for (job = jobList->head; job->next; job = job->next); + job->next = malloc(sizeof(*job)); + job = job->next; + } + + *job = newJob; + job->next = NULL; + job->runningProgs = job->numProgs; + job->stoppedProgs = 0; + + if (inBg) { + /* we don't wait for background jobs to return -- append it + to the list of backgrounded jobs and leave it alone */ + + printf("[%d] %d\n", job->jobId, + newJob.progs[newJob.numProgs - 1].pid); + } else { + jobList->fg = job; + + /* move the new process group into the foreground */ + + if (tcsetpgrp(0, newJob.pgrp)) + perror("tcsetpgrp"); + } + + return 0; +} + +static int setupRedirections(struct childProgram * prog) +{ + int i; + int openfd; + int mode=O_RDONLY; + struct redirectionSpecifier * redir = prog->redirections; + + for (i = 0; i < prog->numRedirections; i++, redir++) { + switch (redir->type) { + case REDIRECT_INPUT: + mode = O_RDONLY; + break; + case REDIRECT_OVERWRITE: + mode = O_RDWR | O_CREAT | O_TRUNC; + break; + case REDIRECT_APPEND: + mode = O_RDWR | O_CREAT | O_APPEND; + break; + } + + openfd = open(redir->filename, mode, 0666); + if (openfd < 0) { + /* this could get lost if stderr has been redirected, but + bash and ash both lose it as well (though zsh doesn't!) */ + fprintf(stderr, "error opening %s: %s\n", redir->filename, + strerror(errno)); + return 1; + } + + if (openfd != redir->fd) { + dup2(openfd, redir->fd); + close(openfd); + } + } + + return 0; +} + + +static int busy_loop(FILE * input) +{ + char command[MAX_COMMAND_LEN + 1]; + char * nextCommand = NULL; + struct jobSet jobList = { NULL, NULL }; + struct job newJob; + int i; + int status; + int inBg; + + /* don't pay any attention to this signal; it just confuses + things and isn't really meant for shells anyway */ + signal(SIGTTOU, SIG_IGN); + + while (1) { + if (!jobList.fg) { + /* no job is in the foreground */ + + /* see if any background processes have exited */ + checkJobs(&jobList); + + if (!nextCommand) { + if (getCommand(input, command)) break; + nextCommand = command; + } + + if (!parseCommand(&nextCommand, &newJob, &inBg) && + newJob.numProgs) { + runCommand(newJob, &jobList, inBg); + } + } else { + /* a job is running in the foreground; wait for it */ + i = 0; + while (!jobList.fg->progs[i].pid || + jobList.fg->progs[i].isStopped) i++; + + waitpid(jobList.fg->progs[i].pid, &status, WUNTRACED); + + if (WIFEXITED(status) || WIFSIGNALED(status)) { + /* the child exited */ + jobList.fg->runningProgs--; + jobList.fg->progs[i].pid = 0; + + if (!jobList.fg->runningProgs) { + /* child exited */ + + removeJob(&jobList, jobList.fg); + jobList.fg = NULL; + + /* move the shell to the foreground */ + if (tcsetpgrp(0, getpid())) + perror("tcsetpgrp"); + } + } else { + /* the child was stopped */ + jobList.fg->stoppedProgs++; + jobList.fg->progs[i].isStopped = 1; + + if (jobList.fg->stoppedProgs == jobList.fg->runningProgs) { + printf("\n" JOB_STATUS_FORMAT, jobList.fg->jobId, + "Stopped", jobList.fg->text); + jobList.fg = NULL; + } + } + + if (!jobList.fg) { + /* move the shell to the foreground */ + if (tcsetpgrp(0, getpid())) + perror("tcsetpgrp"); + } + } + } + + return 0; +} + + +int shell_main(int argc, char ** argv) +{ + FILE * input = stdin; + + if (argc > 2) { + usage( shell_usage); + } + /* initialize the cwd */ + getcwd(cwd, sizeof(cwd)); + + + //if (argv[0] && argv[0][0] == '-') { + // shell_source("/etc/profile"); + //} + + if (argc < 2) { + fprintf(stdout, "\n\nBusyBox v%s (%s) Built-in shell\n", BB_VER, BB_BT); + fprintf(stdout, "Enter 'help' for a list of built-in commands.\n\n"); + } else { + input = fopen(argv[1], "r"); + if (!input) + fatalError("A: Couldn't open file '%s': %s\n", argv[1], strerror(errno)); +// else +// fatalError("Got it.\n"); + //exit(shell_source(argv[1])); + } + + return (busy_loop( input)); +} diff --git a/shell/lash.c b/shell/lash.c new file mode 100644 index 000000000..9e467dc54 --- /dev/null +++ b/shell/lash.c @@ -0,0 +1,915 @@ +/* vi: set sw=4 ts=4: */ +/* + * BusyBox Shell + * + * Copyright (C) 2000 by Lineo, inc. + * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org> + * + * Based in part on ladsh.c by Michael K. Johnson and Erik W. Troan, which is + * under the following liberal license: "We have placed this source code in the + * public domain. Use it in any project, free or commercial." + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include "internal.h" +#include <stdio.h> +#include <stdlib.h> +#include <ctype.h> +#include <errno.h> +#include <fcntl.h> +#include <glob.h> +#include <signal.h> +#include <string.h> +#include <sys/ioctl.h> +#include <sys/wait.h> +#include <unistd.h> + + +#define MAX_COMMAND_LEN 250 /* max length of a single command + string */ +#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n" + +enum redirectionType { REDIRECT_INPUT, REDIRECT_OVERWRITE, REDIRECT_APPEND }; + +struct jobSet { + struct job * head; /* head of list of running jobs */ + struct job * fg; /* current foreground job */ +}; + +struct redirectionSpecifier { + enum redirectionType type; /* type of redirection */ + int fd; /* file descriptor being redirected */ + char * filename; /* file to redirect fd to */ +}; + +struct childProgram { + pid_t pid; /* 0 if exited */ + char ** argv; /* program name and arguments */ + int numRedirections; /* elements in redirection array */ + struct redirectionSpecifier * redirections; /* I/O redirections */ + glob_t globResult; /* result of parameter globbing */ + int freeGlob; /* should we globfree(&globResult)? */ + int isStopped; /* is the program currently running? */ +}; + +struct job { + int jobId; /* job number */ + int numProgs; /* total number of programs in job */ + int runningProgs; /* number of programs running */ + char * text; /* name of job */ + char * cmdBuf; /* buffer various argv's point into */ + pid_t pgrp; /* process group ID for the job */ + struct childProgram * progs; /* array of programs in job */ + struct job * next; /* to track background commands */ + int stoppedProgs; /* number of programs alive, but stopped */ +}; + +struct builtInCommand { + char *cmd; /* name */ + char *descr; /* description */ + char *usage; /* usage */ + int (*function) (struct job *, struct jobSet * jobList); /* function ptr */ +}; + +/* Some function prototypes */ +static int shell_cd(struct job* cmd, struct jobSet* junk); +static int shell_env(struct job* dummy, struct jobSet* junk); +static int shell_exit(struct job* cmd, struct jobSet* junk); +static int shell_fg_bg(struct job* cmd, struct jobSet* jobList); +static int shell_help(struct job* cmd, struct jobSet* junk); +static int shell_jobs(struct job* dummy, struct jobSet* jobList); +static int shell_pwd(struct job* dummy, struct jobSet* junk); +static int shell_set(struct job* cmd, struct jobSet* junk); +static int shell_source(struct job* cmd, struct jobSet* jobList); +static int shell_unset(struct job* cmd, struct jobSet* junk); + +static void checkJobs(struct jobSet * jobList); +static int getCommand(FILE * source, char * command); +static int parseCommand(char ** commandPtr, struct job * job, int * isBg); +static int setupRedirections(struct childProgram * prog); +static int runCommand(struct job newJob, struct jobSet * jobList, int inBg); +static int busy_loop(FILE * input); + + +/* Table of built-in functions */ +static struct builtInCommand bltins[] = { + {"bg", "Resume a job in the background", "bg [%%job]", shell_fg_bg}, + {"cd", "Change working directory", "cd [dir]", shell_cd}, + {"env", "Print all environment variables", "env", shell_env}, + {"exit", "Exit from shell()", "exit", shell_exit}, + {"fg", "Bring job into the foreground", "fg [%%job]", shell_fg_bg}, + {"jobs", "Lists the active jobs", "jobs", shell_jobs}, + {"pwd", "Print current directory", "pwd", shell_pwd}, + {"set", "Set environment variable", "set [VAR=value]", shell_set}, + {"unset", "Unset environment variable", "unset VAR", shell_unset}, + //{"echo", "Echo arguments on stdout", "echo arg1 [...]", shell_echo}, + {".", "Source-in and run commands in a file", ". filename", shell_source}, + {"help", "List shell built-in commands", "help", shell_help}, + {NULL, NULL, NULL, NULL} +}; + +static const char shell_usage[] = + "sh [FILE]...\n\n" + "The BusyBox command interpreter (shell).\n\n"; + + +static char cwd[1024]; +static char *prompt = "# "; + + +/* built-in 'cd <path>' handler */ +static int shell_cd(struct job* cmd, struct jobSet* junk) +{ + char *newdir; + if (!cmd->progs[0].argv[1] == 1) + newdir = getenv("HOME"); + else + newdir = cmd->progs[0].argv[1]; + if (chdir(newdir)) { + printf("cd: %s: %s\n", newdir, strerror(errno)); + return FALSE; + } + getcwd(cwd, sizeof(cwd)); + + return TRUE; +} + +/* built-in 'env' handler */ +static int shell_env(struct job* dummy, struct jobSet* junk) +{ + char **e; + + for (e = environ ; *e ; e++) { + fprintf(stdout, "%s\n", *e); + } + return (0); +} + +/* built-in 'exit' handler */ +static int shell_exit(struct job* cmd, struct jobSet* junk) +{ + if (!cmd->progs[0].argv[1] == 1) + exit TRUE; + else + exit(atoi(cmd->progs[0].argv[1])); +} + +/* built-in 'fg' and 'bg' handler */ +static int shell_fg_bg(struct job* cmd, struct jobSet* jobList) +{ + int i, jobNum; + struct job* job; + + if (!cmd->progs[0].argv[1] || cmd->progs[0].argv[2]) { + fprintf(stderr, "%s: exactly one argument is expected\n", + cmd->progs[0].argv[0]); + return FALSE; + } + + if (sscanf(cmd->progs[0].argv[1], "%%%d", &jobNum) != 1) { + fprintf(stderr, "%s: bad argument '%s'\n", + cmd->progs[0].argv[0], cmd->progs[0].argv[1]); + return FALSE; + } + + for (job = jobList->head; job; job = job->next) + if (job->jobId == jobNum) break; + + if (!job) { + fprintf(stderr, "%s: unknown job %d\n", + cmd->progs[0].argv[0], jobNum); + return FALSE; + } + + if (*cmd->progs[0].argv[0] == 'f') { + /* Make this job the foreground job */ + + if (tcsetpgrp(0, job->pgrp)) + perror("tcsetpgrp"); + jobList->fg = job; + } + + /* Restart the processes in the job */ + for (i = 0; i < job->numProgs; i++) + job->progs[i].isStopped = 0; + + kill(-job->pgrp, SIGCONT); + + job->stoppedProgs = 0; + + return TRUE; +} + +/* built-in 'help' handler */ +static int shell_help(struct job* cmd, struct jobSet* junk) +{ + struct builtInCommand *x; + + fprintf(stdout, "\nBuilt-in commands:\n"); + fprintf(stdout, "-------------------\n"); + for ( x=bltins; x->cmd; x++) { + fprintf(stdout, "%s\t%s\n", x->cmd, x->descr); + } + fprintf(stdout, "\n\n"); + return TRUE; +} + +/* built-in 'jobs' handler */ +static int shell_jobs(struct job* dummy, struct jobSet* jobList) +{ + struct job * job; + char * statusString; + for (job = jobList->head; job; job = job->next) { + if (job->runningProgs == job->stoppedProgs) + statusString = "Stopped"; + else + statusString = "Running"; + + printf(JOB_STATUS_FORMAT, job->jobId, statusString, + job->text); + } + return TRUE; +} + + +/* built-in 'pwd' handler */ +static int shell_pwd(struct job* dummy, struct jobSet* junk) +{ + getcwd(cwd, sizeof(cwd)); + fprintf(stdout, "%s\n", cwd); + return TRUE; +} + +/* built-in 'set VAR=value' handler */ +static int shell_set(struct job* cmd, struct jobSet* junk) +{ + int res; + + if (!cmd->progs[0].argv[1] == 1) { + return (shell_env(cmd, junk)); + } + res = putenv(cmd->progs[0].argv[1]); + if (res) + fprintf(stdout, "set: %s\n", strerror(errno)); + return (res); +} + +/* Built-in '.' handler (read-in and execute commands from file) */ +static int shell_source(struct job* cmd, struct jobSet* junk) +{ + FILE *input; + int status; + + if (!cmd->progs[0].argv[1] == 1) + return FALSE; + + input = fopen(cmd->progs[0].argv[1], "r"); + if (!input) { + fprintf(stdout, "Couldn't open file '%s'\n", cmd->progs[0].argv[1]); + return FALSE; + } + + /* Now run the file */ + status = busy_loop(input); + return (status); +} + +/* built-in 'unset VAR' handler */ +static int shell_unset(struct job* cmd, struct jobSet* junk) +{ + if (!cmd->progs[0].argv[1] == 1) { + fprintf(stdout, "unset: parameter required.\n"); + return FALSE; + } + unsetenv(cmd->progs[0].argv[1]); + return TRUE; +} + +/* free up all memory from a job */ +static void freeJob(struct job * cmd) +{ + int i; + + for (i = 0; i < cmd->numProgs; i++) { + free(cmd->progs[i].argv); + if (cmd->progs[i].redirections) free(cmd->progs[i].redirections); + if (cmd->progs[i].freeGlob) globfree(&cmd->progs[i].globResult); + } + free(cmd->progs); + if (cmd->text) free(cmd->text); + free(cmd->cmdBuf); +} + +/* remove a job from the jobList */ +static void removeJob(struct jobSet * jobList, struct job * job) +{ + struct job * prevJob; + + freeJob(job); + if (job == jobList->head) { + jobList->head = job->next; + } else { + prevJob = jobList->head; + while (prevJob->next != job) prevJob = prevJob->next; + prevJob->next = job->next; + } + + free(job); +} + +/* Checks to see if any background processes have exited -- if they + have, figure out why and see if a job has completed */ +static void checkJobs(struct jobSet * jobList) +{ + struct job * job; + pid_t childpid; + int status; + int progNum=0; + + while ((childpid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) { + for (job = jobList->head; job; job = job->next) { + progNum = 0; + while (progNum < job->numProgs && + job->progs[progNum].pid != childpid) + progNum++; + if (progNum < job->numProgs) break; + } + + if (WIFEXITED(status) || WIFSIGNALED(status)) { + /* child exited */ + job->runningProgs--; + job->progs[progNum].pid = 0; + + if (!job->runningProgs) { + printf(JOB_STATUS_FORMAT, job->jobId, "Done", job->text); + removeJob(jobList, job); + } + } else { + /* child stopped */ + job->stoppedProgs++; + job->progs[progNum].isStopped = 1; + + if (job->stoppedProgs == job->numProgs) { + printf(JOB_STATUS_FORMAT, job->jobId, "Stopped", job->text); + } + } + } + + if (childpid == -1 && errno != ECHILD) + perror("waitpid"); +} + +static int getCommand(FILE * source, char * command) +{ + if (source == stdin) { + fprintf(stdout, "%s %s", cwd, prompt); + fflush(stdout); + } + + if (!fgets(command, MAX_COMMAND_LEN, source)) { + if (source == stdin) printf("\n"); + return 1; + } + + /* remove trailing newline */ + command[strlen(command) - 1] = '\0'; + + return 0; +} + +static void globLastArgument(struct childProgram * prog, int * argcPtr, + int * argcAllocedPtr) +{ + int argc = *argcPtr; + int argcAlloced = *argcAllocedPtr; + int rc; + int flags; + int i; + char * src, * dst; + + if (argc > 1) { /* cmd->globResult is already initialized */ + flags = GLOB_APPEND; + i = prog->globResult.gl_pathc; + } else { + prog->freeGlob = 1; + flags = 0; + i = 0; + } + + rc = glob(prog->argv[argc - 1], flags, NULL, &prog->globResult); + if (rc == GLOB_NOSPACE) { + fprintf(stderr, "out of space during glob operation\n"); + return; + } else if (rc == GLOB_NOMATCH || + (!rc && (prog->globResult.gl_pathc - i) == 1 && + !strcmp(prog->argv[argc - 1], + prog->globResult.gl_pathv[i]))) { + /* we need to remove whatever \ quoting is still present */ + src = dst = prog->argv[argc - 1]; + while (*src) { + if (*src != '\\') *dst++ = *src; + src++; + } + *dst = '\0'; + } else if (!rc) { + argcAlloced += (prog->globResult.gl_pathc - i); + prog->argv = realloc(prog->argv, argcAlloced * sizeof(*prog->argv)); + memcpy(prog->argv + (argc - 1), prog->globResult.gl_pathv + i, + sizeof(*(prog->argv)) * (prog->globResult.gl_pathc - i)); + argc += (prog->globResult.gl_pathc - i - 1); + } + + *argcAllocedPtr = argcAlloced; + *argcPtr = argc; +} + +/* Return cmd->numProgs as 0 if no command is present (e.g. an empty + line). If a valid command is found, commandPtr is set to point to + the beginning of the next command (if the original command had more + then one job associated with it) or NULL if no more commands are + present. */ +static int parseCommand(char ** commandPtr, struct job * job, int * isBg) +{ + char * command; + char * returnCommand = NULL; + char * src, * buf, * chptr; + int argc = 0; + int done = 0; + int argvAlloced; + int i; + char quote = '\0'; + int count; + struct childProgram * prog; + + /* skip leading white space */ + while (**commandPtr && isspace(**commandPtr)) (*commandPtr)++; + + /* this handles empty lines or leading '#' characters */ + if (!**commandPtr || (**commandPtr=='#')) { + job->numProgs = 0; + *commandPtr = NULL; + return 0; + } + + *isBg = 0; + job->numProgs = 1; + job->progs = malloc(sizeof(*job->progs)); + + /* We set the argv elements to point inside of this string. The + memory is freed by freeJob(). + + Getting clean memory relieves us of the task of NULL + terminating things and makes the rest of this look a bit + cleaner (though it is, admittedly, a tad less efficient) */ + job->cmdBuf = command = calloc(1, strlen(*commandPtr) + 1); + job->text = NULL; + + prog = job->progs; + prog->numRedirections = 0; + prog->redirections = NULL; + prog->freeGlob = 0; + prog->isStopped = 0; + + argvAlloced = 5; + prog->argv = malloc(sizeof(*prog->argv) * argvAlloced); + prog->argv[0] = job->cmdBuf; + + buf = command; + src = *commandPtr; + while (*src && !done) { + if (quote == *src) { + quote = '\0'; + } else if (quote) { + if (*src == '\\') { + src++; + if (!*src) { + fprintf(stderr, "character expected after \\\n"); + freeJob(job); + return 1; + } + + /* in shell, "\'" should yield \' */ + if (*src != quote) *buf++ = '\\'; + } else if (*src == '*' || *src == '?' || *src == '[' || + *src == ']') + *buf++ = '\\'; + *buf++ = *src; + } else if (isspace(*src)) { + if (*prog->argv[argc]) { + buf++, argc++; + /* +1 here leaves room for the NULL which ends argv */ + if ((argc + 1) == argvAlloced) { + argvAlloced += 5; + prog->argv = realloc(prog->argv, + sizeof(*prog->argv) * argvAlloced); + } + prog->argv[argc] = buf; + + globLastArgument(prog, &argc, &argvAlloced); + } + } else switch (*src) { + case '"': + case '\'': + quote = *src; + break; + + case '#': /* comment */ + done = 1; + break; + + case '>': /* redirections */ + case '<': + i = prog->numRedirections++; + prog->redirections = realloc(prog->redirections, + sizeof(*prog->redirections) * (i + 1)); + + prog->redirections[i].fd = -1; + if (buf != prog->argv[argc]) { + /* the stuff before this character may be the file number + being redirected */ + prog->redirections[i].fd = strtol(prog->argv[argc], &chptr, 10); + + if (*chptr && *prog->argv[argc]) { + buf++, argc++; + globLastArgument(prog, &argc, &argvAlloced); + } + } + + if (prog->redirections[i].fd == -1) { + if (*src == '>') + prog->redirections[i].fd = 1; + else + prog->redirections[i].fd = 0; + } + + if (*src++ == '>') { + if (*src == '>') + prog->redirections[i].type = REDIRECT_APPEND, src++; + else + prog->redirections[i].type = REDIRECT_OVERWRITE; + } else { + prog->redirections[i].type = REDIRECT_INPUT; + } + + /* This isn't POSIX sh compliant. Oh well. */ + chptr = src; + while (isspace(*chptr)) chptr++; + + if (!*chptr) { + fprintf(stderr, "file name expected after %c\n", *src); + freeJob(job); + return 1; + } + + prog->redirections[i].filename = buf; + while (*chptr && !isspace(*chptr)) + *buf++ = *chptr++; + + src = chptr - 1; /* we src++ later */ + prog->argv[argc] = ++buf; + break; + + case '|': /* pipe */ + /* finish this command */ + if (*prog->argv[argc]) argc++; + if (!argc) { + fprintf(stderr, "empty command in pipe\n"); + freeJob(job); + return 1; + } + prog->argv[argc] = NULL; + + /* and start the next */ + job->numProgs++; + job->progs = realloc(job->progs, + sizeof(*job->progs) * job->numProgs); + prog = job->progs + (job->numProgs - 1); + prog->numRedirections = 0; + prog->redirections = NULL; + prog->freeGlob = 0; + argc = 0; + + argvAlloced = 5; + prog->argv = malloc(sizeof(*prog->argv) * argvAlloced); + prog->argv[0] = ++buf; + + src++; + while (*src && isspace(*src)) src++; + + if (!*src) { + fprintf(stderr, "empty command in pipe\n"); + return 1; + } + src--; /* we'll ++ it at the end of the loop */ + + break; + + case '&': /* background */ + *isBg = 1; + case ';': /* multiple commands */ + done = 1; + returnCommand = *commandPtr + (src - *commandPtr) + 1; + break; + + case '\\': + src++; + if (!*src) { + freeJob(job); + fprintf(stderr, "character expected after \\\n"); + return 1; + } + if (*src == '*' || *src == '[' || *src == ']' || *src == '?') + *buf++ = '\\'; + /* fallthrough */ + default: + *buf++ = *src; + } + + src++; + } + + if (*prog->argv[argc]) { + argc++; + globLastArgument(prog, &argc, &argvAlloced); + } + if (!argc) { + freeJob(job); + return 0; + } + prog->argv[argc] = NULL; + + if (!returnCommand) { + job->text = malloc(strlen(*commandPtr) + 1); + strcpy(job->text, *commandPtr); + } else { + /* This leaves any trailing spaces, which is a bit sloppy */ + + count = returnCommand - *commandPtr; + job->text = malloc(count + 1); + strncpy(job->text, *commandPtr, count); + job->text[count] = '\0'; + } + + *commandPtr = returnCommand; + + return 0; +} + +static int runCommand(struct job newJob, struct jobSet * jobList, + int inBg) +{ + struct job * job; + int i; + int nextin, nextout; + int pipefds[2]; /* pipefd[0] is for reading */ + struct builtInCommand *x; + + /* handle built-ins here -- we don't fork() so we can't background + these very easily */ + for( x=bltins ; x->cmd ; x++) { + if (!strcmp(newJob.progs[0].argv[0], x->cmd)) { + return(x->function(&newJob, jobList)); + } + } + + nextin = 0, nextout = 1; + for (i = 0; i < newJob.numProgs; i++) { + if ((i + 1) < newJob.numProgs) { + pipe(pipefds); + nextout = pipefds[1]; + } else { + nextout = 1; + } + + if (!(newJob.progs[i].pid = fork())) { + signal(SIGTTOU, SIG_DFL); + + if (nextin != 0) { + dup2(nextin, 0); + close(nextin); + } + + if (nextout != 1) { + dup2(nextout, 1); + close(nextout); + } + + /* explicit redirections override pipes */ + setupRedirections(newJob.progs + i); + + execvp(newJob.progs[i].argv[0], newJob.progs[i].argv); + fatalError( "sh: %s: %s\n", newJob.progs[i].argv[0], + strerror(errno)); + } + + /* put our child in the process group whose leader is the + first process in this pipe */ + setpgid(newJob.progs[i].pid, newJob.progs[0].pid); + + if (nextin != 0) close(nextin); + if (nextout != 1) close(nextout); + + /* If there isn't another process, nextin is garbage + but it doesn't matter */ + nextin = pipefds[0]; + } + + newJob.pgrp = newJob.progs[0].pid; + + /* find the ID for the job to use */ + newJob.jobId = 1; + for (job = jobList->head; job; job = job->next) + if (job->jobId >= newJob.jobId) + newJob.jobId = job->jobId + 1; + + /* add the job to the list of running jobs */ + if (!jobList->head) { + job = jobList->head = malloc(sizeof(*job)); + } else { + for (job = jobList->head; job->next; job = job->next); + job->next = malloc(sizeof(*job)); + job = job->next; + } + + *job = newJob; + job->next = NULL; + job->runningProgs = job->numProgs; + job->stoppedProgs = 0; + + if (inBg) { + /* we don't wait for background jobs to return -- append it + to the list of backgrounded jobs and leave it alone */ + + printf("[%d] %d\n", job->jobId, + newJob.progs[newJob.numProgs - 1].pid); + } else { + jobList->fg = job; + + /* move the new process group into the foreground */ + + if (tcsetpgrp(0, newJob.pgrp)) + perror("tcsetpgrp"); + } + + return 0; +} + +static int setupRedirections(struct childProgram * prog) +{ + int i; + int openfd; + int mode=O_RDONLY; + struct redirectionSpecifier * redir = prog->redirections; + + for (i = 0; i < prog->numRedirections; i++, redir++) { + switch (redir->type) { + case REDIRECT_INPUT: + mode = O_RDONLY; + break; + case REDIRECT_OVERWRITE: + mode = O_RDWR | O_CREAT | O_TRUNC; + break; + case REDIRECT_APPEND: + mode = O_RDWR | O_CREAT | O_APPEND; + break; + } + + openfd = open(redir->filename, mode, 0666); + if (openfd < 0) { + /* this could get lost if stderr has been redirected, but + bash and ash both lose it as well (though zsh doesn't!) */ + fprintf(stderr, "error opening %s: %s\n", redir->filename, + strerror(errno)); + return 1; + } + + if (openfd != redir->fd) { + dup2(openfd, redir->fd); + close(openfd); + } + } + + return 0; +} + + +static int busy_loop(FILE * input) +{ + char command[MAX_COMMAND_LEN + 1]; + char * nextCommand = NULL; + struct jobSet jobList = { NULL, NULL }; + struct job newJob; + int i; + int status; + int inBg; + + /* don't pay any attention to this signal; it just confuses + things and isn't really meant for shells anyway */ + signal(SIGTTOU, SIG_IGN); + + while (1) { + if (!jobList.fg) { + /* no job is in the foreground */ + + /* see if any background processes have exited */ + checkJobs(&jobList); + + if (!nextCommand) { + if (getCommand(input, command)) break; + nextCommand = command; + } + + if (!parseCommand(&nextCommand, &newJob, &inBg) && + newJob.numProgs) { + runCommand(newJob, &jobList, inBg); + } + } else { + /* a job is running in the foreground; wait for it */ + i = 0; + while (!jobList.fg->progs[i].pid || + jobList.fg->progs[i].isStopped) i++; + + waitpid(jobList.fg->progs[i].pid, &status, WUNTRACED); + + if (WIFEXITED(status) || WIFSIGNALED(status)) { + /* the child exited */ + jobList.fg->runningProgs--; + jobList.fg->progs[i].pid = 0; + + if (!jobList.fg->runningProgs) { + /* child exited */ + + removeJob(&jobList, jobList.fg); + jobList.fg = NULL; + + /* move the shell to the foreground */ + if (tcsetpgrp(0, getpid())) + perror("tcsetpgrp"); + } + } else { + /* the child was stopped */ + jobList.fg->stoppedProgs++; + jobList.fg->progs[i].isStopped = 1; + + if (jobList.fg->stoppedProgs == jobList.fg->runningProgs) { + printf("\n" JOB_STATUS_FORMAT, jobList.fg->jobId, + "Stopped", jobList.fg->text); + jobList.fg = NULL; + } + } + + if (!jobList.fg) { + /* move the shell to the foreground */ + if (tcsetpgrp(0, getpid())) + perror("tcsetpgrp"); + } + } + } + + return 0; +} + + +int shell_main(int argc, char ** argv) +{ + FILE * input = stdin; + + if (argc > 2) { + usage( shell_usage); + } + /* initialize the cwd */ + getcwd(cwd, sizeof(cwd)); + + + //if (argv[0] && argv[0][0] == '-') { + // shell_source("/etc/profile"); + //} + + if (argc < 2) { + fprintf(stdout, "\n\nBusyBox v%s (%s) Built-in shell\n", BB_VER, BB_BT); + fprintf(stdout, "Enter 'help' for a list of built-in commands.\n\n"); + } else { + input = fopen(argv[1], "r"); + if (!input) + fatalError("A: Couldn't open file '%s': %s\n", argv[1], strerror(errno)); +// else +// fatalError("Got it.\n"); + //exit(shell_source(argv[1])); + } + + return (busy_loop( input)); +} @@ -96,8 +96,8 @@ extern void errorMsg(char *s, ...) va_start(p, s); fflush(stdout); vfprintf(stderr, s, p); - fprintf(stderr, "\n"); va_end(p); + fflush(stderr); } extern void fatalError(char *s, ...) @@ -107,8 +107,8 @@ extern void fatalError(char *s, ...) va_start(p, s); fflush(stdout); vfprintf(stderr, s, p); - fprintf(stderr, "\n"); va_end(p); + fflush(stderr); exit( FALSE); } |