diff options
| -rw-r--r-- | hush.c | 73 | ||||
| -rw-r--r-- | shell/hush.c | 73 |
2 files changed, 108 insertions, 38 deletions
@@ -45,24 +45,25 @@ * fancy forms of Parameter Expansion * Arithmetic Expansion * <(list) and >(list) Process Substitution - * reserved words: case, esac, function + * reserved words: case, esac, select, function * Here Documents ( << word ) * Functions * Major bugs: * job handling woefully incomplete and buggy * reserved word execution woefully incomplete and buggy * to-do: - * port selected bugfixes from post-0.49 busybox lash - * finish implementing reserved words + * port selected bugfixes from post-0.49 busybox lash - done? + * finish implementing reserved words: for, while, until, do, done + * change { and } from special chars to reserved words + * builtins: break, continue, eval, return, set, trap, ulimit + * test magic exec * handle children going into background * clean up recognition of null pipes * have builtin_exec set flag to avoid restore_redirects - * figure out if "echo foo}" is fixable * check setting of global_argc and global_argv * control-C handling, probably with longjmp * VAR=value prefix for simple commands * follow IFS rules more precisely, including update semantics - * write builtin_eval, builtin_ulimit, builtin_umask * figure out what to do with backslash-newline * explain why we use signal instead of sigaction * propagate syntax errors, die on resource errors? @@ -97,6 +98,7 @@ #include <fcntl.h> #include <getopt.h> /* should be pretty obvious */ +#include <sys/stat.h> /* ulimit */ #include <sys/types.h> #include <sys/wait.h> #include <signal.h> @@ -323,9 +325,9 @@ static int builtin_pwd(struct child_prog *child); static int builtin_read(struct child_prog *child); static int builtin_shift(struct child_prog *child); static int builtin_source(struct child_prog *child); -static int builtin_ulimit(struct child_prog *child); static int builtin_umask(struct child_prog *child); static int builtin_unset(struct child_prog *child); +static int builtin_not_written(struct child_prog *child); /* o_string manipulation: */ static int b_check_space(o_string *o, int len); static int b_addchr(o_string *o, int ch); @@ -390,8 +392,11 @@ static void free_pipe(struct pipe *pi); * still be set at the end. */ static struct built_in_command bltins[] = { {"bg", "Resume a job in the background", builtin_fg_bg}, + {"break", "Exit for, while or until loop", builtin_not_written}, {"cd", "Change working directory", builtin_cd}, + {"continue", "Continue for, while or until loop", builtin_not_written}, {"env", "Print all environment variables", builtin_env}, + {"eval", "Construct and run shell command", builtin_not_written}, {"exec", "Exec command, replacing this shell with the exec'd process", builtin_exec}, {"exit", "Exit from shell()", builtin_exit}, {"export", "Set environment variable", builtin_export}, @@ -399,8 +404,11 @@ static struct built_in_command bltins[] = { {"jobs", "Lists the active jobs", builtin_jobs}, {"pwd", "Print current directory", builtin_pwd}, {"read", "Input environment variable", builtin_read}, + {"return", "Return from a function", builtin_not_written}, + {"set", "Set/unset shell options", builtin_not_written}, {"shift", "Shift positional parameters", builtin_shift}, - {"ulimit","Controls resource limits", builtin_ulimit}, + {"trap", "Trap signals", builtin_not_written}, + {"ulimit","Controls resource limits", builtin_not_written}, {"umask","Sets file creation mask", builtin_umask}, {"unset", "Unset environment variable", builtin_unset}, {".", "Source-in and run commands in a file", builtin_source}, @@ -640,16 +648,21 @@ static int builtin_source(struct child_prog *child) return (status); } -static int builtin_ulimit(struct child_prog *child) -{ - printf("builtin_ulimit not written\n"); - return EXIT_FAILURE; -} - static int builtin_umask(struct child_prog *child) { - printf("builtin_umask not written\n"); - return EXIT_FAILURE; + mode_t new_umask; + const char *arg = child->argv[1]; + char *end; + if (arg) { + new_umask=strtoul(arg, &end, 8); + if (*end!='\0' || end == arg) { + return EXIT_FAILURE; + } + } else { + printf("%.3o\n", (unsigned int) (new_umask=umask(0))); + } + umask(new_umask); + return EXIT_SUCCESS; } /* built-in 'unset VAR' handler */ @@ -663,6 +676,12 @@ static int builtin_unset(struct child_prog *child) return EXIT_SUCCESS; } +static int builtin_not_written(struct child_prog *child) +{ + printf("builtin_%s not written\n",child->argv[0]); + return EXIT_FAILURE; +} + static int b_check_space(o_string *o, int len) { /* It would be easy to drop a more restrictive policy @@ -926,8 +945,12 @@ static int setup_redirects(struct child_prog *prog, int squirrel[]) if (squirrel && redir->fd < 3) { squirrel[redir->fd] = dup(redir->fd); } - dup2(openfd, redir->fd); - close(openfd); + if (openfd == -3) { + close(openfd); + } else { + dup2(openfd, redir->fd); + close(openfd); + } } } return 0; @@ -1216,6 +1239,11 @@ static int run_pipe_real(struct pipe *pi) if (strcmp(child->argv[0], x->cmd) == 0 ) { int squirrel[] = {-1, -1, -1}; int rcode; + if (x->function == builtin_exec && child->argv[1]==NULL) { + debug_printf("magic exec\n"); + setup_redirects(child,NULL); + return EXIT_SUCCESS; + } debug_printf("builtin inline %s\n", child->argv[0]); /* XXX setup_redirects acts on file descriptors, not FILEs. * This is perfect for work that comes after exec(). @@ -1569,7 +1597,8 @@ static int setup_redirect(struct p_context *ctx, int fd, redir_type style, if (redir->dup == -2) return 1; /* syntax error */ if (redir->dup != -1) { /* Erik had a check here that the file descriptor in question - * is legit; I postpone that to "run time" */ + * is legit; I postpone that to "run time" + * A "-" representation of "close me" shows up as a -3 here */ debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup); } else { /* We do _not_ try to open the file that src points to, @@ -1775,10 +1804,16 @@ static int redirect_dup_num(struct in_str *input) if (ch != '&') return -1; b_getch(input); /* get the & */ - while (ch=b_peek(input),isdigit(ch)) { + ch=b_peek(input); + if (ch == '-') { + b_getch(input); + return -3; /* "-" represents "close me" */ + } + while (isdigit(ch)) { d = d*10+(ch-'0'); ok=1; b_getch(input); + ch = b_peek(input); } if (ok) return d; diff --git a/shell/hush.c b/shell/hush.c index b8e4a55c2..e58ac44b3 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -45,24 +45,25 @@ * fancy forms of Parameter Expansion * Arithmetic Expansion * <(list) and >(list) Process Substitution - * reserved words: case, esac, function + * reserved words: case, esac, select, function * Here Documents ( << word ) * Functions * Major bugs: * job handling woefully incomplete and buggy * reserved word execution woefully incomplete and buggy * to-do: - * port selected bugfixes from post-0.49 busybox lash - * finish implementing reserved words + * port selected bugfixes from post-0.49 busybox lash - done? + * finish implementing reserved words: for, while, until, do, done + * change { and } from special chars to reserved words + * builtins: break, continue, eval, return, set, trap, ulimit + * test magic exec * handle children going into background * clean up recognition of null pipes * have builtin_exec set flag to avoid restore_redirects - * figure out if "echo foo}" is fixable * check setting of global_argc and global_argv * control-C handling, probably with longjmp * VAR=value prefix for simple commands * follow IFS rules more precisely, including update semantics - * write builtin_eval, builtin_ulimit, builtin_umask * figure out what to do with backslash-newline * explain why we use signal instead of sigaction * propagate syntax errors, die on resource errors? @@ -97,6 +98,7 @@ #include <fcntl.h> #include <getopt.h> /* should be pretty obvious */ +#include <sys/stat.h> /* ulimit */ #include <sys/types.h> #include <sys/wait.h> #include <signal.h> @@ -323,9 +325,9 @@ static int builtin_pwd(struct child_prog *child); static int builtin_read(struct child_prog *child); static int builtin_shift(struct child_prog *child); static int builtin_source(struct child_prog *child); -static int builtin_ulimit(struct child_prog *child); static int builtin_umask(struct child_prog *child); static int builtin_unset(struct child_prog *child); +static int builtin_not_written(struct child_prog *child); /* o_string manipulation: */ static int b_check_space(o_string *o, int len); static int b_addchr(o_string *o, int ch); @@ -390,8 +392,11 @@ static void free_pipe(struct pipe *pi); * still be set at the end. */ static struct built_in_command bltins[] = { {"bg", "Resume a job in the background", builtin_fg_bg}, + {"break", "Exit for, while or until loop", builtin_not_written}, {"cd", "Change working directory", builtin_cd}, + {"continue", "Continue for, while or until loop", builtin_not_written}, {"env", "Print all environment variables", builtin_env}, + {"eval", "Construct and run shell command", builtin_not_written}, {"exec", "Exec command, replacing this shell with the exec'd process", builtin_exec}, {"exit", "Exit from shell()", builtin_exit}, {"export", "Set environment variable", builtin_export}, @@ -399,8 +404,11 @@ static struct built_in_command bltins[] = { {"jobs", "Lists the active jobs", builtin_jobs}, {"pwd", "Print current directory", builtin_pwd}, {"read", "Input environment variable", builtin_read}, + {"return", "Return from a function", builtin_not_written}, + {"set", "Set/unset shell options", builtin_not_written}, {"shift", "Shift positional parameters", builtin_shift}, - {"ulimit","Controls resource limits", builtin_ulimit}, + {"trap", "Trap signals", builtin_not_written}, + {"ulimit","Controls resource limits", builtin_not_written}, {"umask","Sets file creation mask", builtin_umask}, {"unset", "Unset environment variable", builtin_unset}, {".", "Source-in and run commands in a file", builtin_source}, @@ -640,16 +648,21 @@ static int builtin_source(struct child_prog *child) return (status); } -static int builtin_ulimit(struct child_prog *child) -{ - printf("builtin_ulimit not written\n"); - return EXIT_FAILURE; -} - static int builtin_umask(struct child_prog *child) { - printf("builtin_umask not written\n"); - return EXIT_FAILURE; + mode_t new_umask; + const char *arg = child->argv[1]; + char *end; + if (arg) { + new_umask=strtoul(arg, &end, 8); + if (*end!='\0' || end == arg) { + return EXIT_FAILURE; + } + } else { + printf("%.3o\n", (unsigned int) (new_umask=umask(0))); + } + umask(new_umask); + return EXIT_SUCCESS; } /* built-in 'unset VAR' handler */ @@ -663,6 +676,12 @@ static int builtin_unset(struct child_prog *child) return EXIT_SUCCESS; } +static int builtin_not_written(struct child_prog *child) +{ + printf("builtin_%s not written\n",child->argv[0]); + return EXIT_FAILURE; +} + static int b_check_space(o_string *o, int len) { /* It would be easy to drop a more restrictive policy @@ -926,8 +945,12 @@ static int setup_redirects(struct child_prog *prog, int squirrel[]) if (squirrel && redir->fd < 3) { squirrel[redir->fd] = dup(redir->fd); } - dup2(openfd, redir->fd); - close(openfd); + if (openfd == -3) { + close(openfd); + } else { + dup2(openfd, redir->fd); + close(openfd); + } } } return 0; @@ -1216,6 +1239,11 @@ static int run_pipe_real(struct pipe *pi) if (strcmp(child->argv[0], x->cmd) == 0 ) { int squirrel[] = {-1, -1, -1}; int rcode; + if (x->function == builtin_exec && child->argv[1]==NULL) { + debug_printf("magic exec\n"); + setup_redirects(child,NULL); + return EXIT_SUCCESS; + } debug_printf("builtin inline %s\n", child->argv[0]); /* XXX setup_redirects acts on file descriptors, not FILEs. * This is perfect for work that comes after exec(). @@ -1569,7 +1597,8 @@ static int setup_redirect(struct p_context *ctx, int fd, redir_type style, if (redir->dup == -2) return 1; /* syntax error */ if (redir->dup != -1) { /* Erik had a check here that the file descriptor in question - * is legit; I postpone that to "run time" */ + * is legit; I postpone that to "run time" + * A "-" representation of "close me" shows up as a -3 here */ debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup); } else { /* We do _not_ try to open the file that src points to, @@ -1775,10 +1804,16 @@ static int redirect_dup_num(struct in_str *input) if (ch != '&') return -1; b_getch(input); /* get the & */ - while (ch=b_peek(input),isdigit(ch)) { + ch=b_peek(input); + if (ch == '-') { + b_getch(input); + return -3; /* "-" represents "close me" */ + } + while (isdigit(ch)) { d = d*10+(ch-'0'); ok=1; b_getch(input); + ch = b_peek(input); } if (ok) return d; |