From ae626295bad3e20a9c457f5f616cd92299f5258c Mon Sep 17 00:00:00 2001 From: Rob Landley Date: Sat, 1 Feb 2020 04:16:15 -0600 Subject: Auto-initialize variables, some of which are readonly and some exported. --- toys/pending/sh.c | 278 ++++++++++++++++++++++++++++-------------------------- 1 file changed, 146 insertions(+), 132 deletions(-) (limited to 'toys') diff --git a/toys/pending/sh.c b/toys/pending/sh.c index e84d8dfb..7e6f827d 100644 --- a/toys/pending/sh.c +++ b/toys/pending/sh.c @@ -19,64 +19,22 @@ * * Things like the bash man page are good to read too. * + * deviations from posix: don't care about $LANG or $LC_ALL + * TODO: test that $PS1 color changes work without stupid \[ \] hack - * TODO: make fake pty wrapper for test infrastructure - * TODO: // Handle embedded NUL bytes in the command line. - * existing but considered builtins: kill pwd time + * TODO: Handle embedded NUL bytes in the command line? (When/how?) + * TODO: replace getenv() with faster func: sort env and binary search + * buitins: alias bg command fc fg getopts jobs newgrp read umask unalias wait * disown umask suspend source pushd popd dirs logout times trap * unset local export readonly set : . let history declare * "special" builtins: break continue eval exec return shift * builtins with extra shell behavior: kill pwd time test + * | & ; < > ( ) $ ` \ " ' * * ? [ # ~ = % * ! { } case do done elif else esac fi for if in then until while * [[ ]] function select - * $@ $* $# $? $- $$ $! $0 - * ENV HOME IFS LANG LC_ALL LINENO PATH PPID PS1 PS2 PS4 PWD - -// EUID GROUPS HOSTNAME HOSTTYPE=$(uname -m) MACHTYPE=$HOSTTYPE-unknown-linux -// OLDPWD OSTYPE=linux/android PIPESTATUS PPID PWD RANDOM REPLY SECONDS UID -// COLUMNS LINES HOME SHELL -// IFS PATH -// PS0 PS1='$ ' PS2='> ' PS3 - -ENV - if [ -n "$ENV" ]; then . "$ENV"; fi # BASH_ENV - synonym for ENV -#EXECIGNORE, FIGNORE, GLOBIGNORE -FUNCNEST - maximum function nesting level (abort when above) - -BASH - argv0? -BASHPID - synonym for $$ HERE -BASH_SUBSHELL - SHLVL synonym -BASH_EXECUTION_STRING - -c argument -BASH_VERSION - toybox version - -REPLY - set by input with no args -SHLVL - nested level of subshells, starting with 1 -UID - readonly -EUID - readonly -PPID - readonly - -automatically set: -HOME SHELL HOSTNAME -HOSTTYPE - uname -m -MACHTYPE - $(uname -m)-unknown-linux -OSTYPE - unaem -o -OPTARG - set by getopts builtin -OPTIND - set by getopts builtin -OPTERR -OLDPWD - set by cd each time -PWD - set by cd -COLUMNS LINES - set at start and by winch - -PROMPT_COMMAND PROMPT_DIRTRIM PS0 PS1 PS2 PS3 PS4 - -unsettable (assignments ignored before then) -LINENO SECONDS RANDOM -GROUPS - id -g -HISTCMD - history number - -TMOUT - used by read * label: * TODO: test exit from "trap EXIT" doesn't recurse @@ -90,7 +48,7 @@ TMOUT - used by read * then until while { } time [[ ]] USE_SH(NEWTOY(cd, ">1LP[-LP]", TOYFLAG_NOFORK)) -USE_SH(NEWTOY(exit, NULL, TOYFLAG_NOFORK)) +USE_SH(NEWTOY(exit, 0, TOYFLAG_NOFORK)) USE_SH(NEWTOY(sh, "(noediting)(noprofile)(norc)sc:i", TOYFLAG_BIN)) USE_SH(OLDTOY(toysh, sh, TOYFLAG_BIN)) @@ -140,12 +98,12 @@ config EXIT #include "toys.h" GLOBALS( - char *command; + char *c; long lineno; char **locals, *subshell_env; struct double_list functions; - unsigned options, jobcnt; + unsigned options, jobcnt, loc_ro, loc_magic; int hfd; // next high filehandle (>= 10) // Running jobs. @@ -199,8 +157,6 @@ void array_add(char ***list, unsigned count, char *data) (*list)[count+1] = 0; } -// TODO local variables - // Return index of variable within this list static unsigned findvar(char **list, char *name, int len) { @@ -223,10 +179,7 @@ static void setvar(char *s, unsigned type) unsigned uu; int len = stridx(s, '='); - if (len == -1) { - error_msg("no = in setvar %s\n", s); - return; - } + if (len == -1) return error_msg("no = in setvar %s\n", s); if (type&TAKE_MEM) type ^= TAKE_MEM; else s = xstrdup(s); @@ -237,13 +190,11 @@ static void setvar(char *s, unsigned type) if (environ && environ[uu = findvar(environ, s, len)]) { if (uu>=toys.envc) free(environ[uu]); environ[uu] = s; - } else { - uu = 0; - if (TT.locals && TT.locals[uu = findvar(TT.locals, s, len)]) { - free(TT.locals[uu]); - TT.locals[uu] = s; - } else array_add(&TT.locals, uu, s); - } + } else if (TT.locals[uu = findvar(TT.locals, s, len)]) { + if (uu0) { + s = xstrndup(str, len); + sh_run(s); + free(s); - pid = xpopen_setup(0, 0, subshell_callback); - close(254); + _exit(toys.exitval); + } - if (TT.locals) - for (i = 0; TT.locals[i]; i++) dprintf(pipes[1], "%s\n", TT.locals[i]); - dprintf(pipes[1], "%.*s\n", len, str); - close(pipes[1]); + // On nommu vfork, exec /proc/self/exe, and pipe state data to ourselves. + } else { + int pipes[2], i; + + // open pipe to child + if (pipe(pipes) || 254 != dup2(pipes[0], 254)) return 1; + close(pipes[0]); + fcntl(pipes[1], F_SETFD, FD_CLOEXEC); + + // vfork child + pid = xpopen_setup(0, 0, subshell_callback); + + // marshall data to child + close(254); + if (TT.locals) + for (i = 0; TT.locals[i]; i++) dprintf(pipes[1], "%s\n", TT.locals[i]); + dprintf(pipes[1], "%.*s\n", len, str); + close(pipes[1]); + } return pid; } @@ -924,12 +893,11 @@ if (BUGBUG) { int i; dprintf(255, "envlen=%d arg->c=%d run=", envlen, arg->c); f // Do nothing if nothing to do } else if (pp->exit || !pp->arg.v); - else if (!strcmp(*pp->arg.v, "((")) { - printf("Math!\n"); -// TODO: handle ((math)) +// else if (!strcmp(*pp->arg.v, "((")) +// TODO: handle ((math)) currently totally broken // TODO: call functions() // Is this command a builtin that should run in this process? - } else if ((tl = toy_find(*pp->arg.v)) + else if ((tl = toy_find(*pp->arg.v)) && (tl->flags & (TOYFLAG_NOFORK|TOYFLAG_MAYFORK))) { struct toy_context temp; @@ -951,25 +919,30 @@ if (BUGBUG) { int i; dprintf(255, "envlen=%d arg->c=%d run=", envlen, arg->c); f memcpy(&toys, &temp, sizeof(struct toy_context)); } else { char **env = 0, **old = environ, *ss, *sss; - int kk, ll; - - // Assign leading environment variables - if (envlen) { - kk = 0; - if (environ) while (environ[kk]) kk++; - if (kk) env = xmemdup(environ, sizeof(char *)*(kk+33)); - for (j = 0; jv[j], NO_PATH|NO_SPLIT, &pp->delete); - for (ll = 0; llv[j], NO_PATH|NO_SPLIT, &pp->delete); + for (ll = 0; llpid = xpopen_both(pp->arg.v, 0))) perror_msg("%s: vfork", *pp->arg.v); @@ -1707,14 +1680,7 @@ dprintf(2, "TODO skipped init for((;;)), need math parser\n"); pl = pl->next; } -/* TODO -case/esac -{/} -[[/]] -(/) -((/)) -function/} -*/ +// TODO case/esac {/} [[/]] (/) ((/)) function/} // gearshift from block start to block body (end of flow control test) } else if (pl->type == 2) { @@ -1781,6 +1747,8 @@ static int sh_run(char *new) struct sh_function scratch; int rc; +// TODO switch the fmemopen for -c to use this? Error checking? $(blah) + memset(&scratch, 0, sizeof(struct sh_function)); if (!parse_line(new, &scratch)) run_function(&scratch); free_function(&scratch); @@ -1850,13 +1818,52 @@ static void do_prompt(char *prompt) writeall(2, toybuf, len); } -// sanitize environment and handle nommu subshell handoff -void subshell_imports(void) +// only set local variable when global not present +static void setonlylocal(char ***to, char *name, char *val) +{ + if (getenv(name)) return; + *(*to)++ = xmprintf("%s=%s", name, val ? val : ""); +} + +// init locals, sanitize environment, handle nommu subshell handoff +void subshell_setup(void) { - int to, from, pid = 0, ppid = 0, len; + struct passwd *pw = getpwuid(getuid()); + int to, from, pid = 0, ppid = 0, mypid, myppid, len; + char *s, *ss, **ll, *locals[] = {"GROUPS=", "SECONDS=", "RANDOM=", "LINENO=", + xmprintf("PPID=%d", myppid = getppid()), xmprintf("EUID=%d", geteuid()), + xmprintf("$=%d", mypid = getpid()), xmprintf("UID=%d", getuid())}; struct stat st; + struct utsname uu; FILE *fp; - char *s; + + // Initialize read only local variables + TT.locals = xmalloc(32*sizeof(char *)); + memcpy(TT.locals, locals, sizeof(locals)); + ll = TT.locals+(TT.loc_ro = ARRAY_LEN(locals)); + TT.loc_magic = 4; + + // Add local variables that can be overwritten + setonlylocal(&ll, "PATH", _PATH_DEFPATH); + if (!pw) pw = (void *)toybuf; // first use, so still zeroed + setonlylocal(&ll, "HOME", *pw->pw_dir ? pw->pw_dir : "/"); + setonlylocal(&ll, "SHELL", pw->pw_shell); + setonlylocal(&ll, "USER", pw->pw_name); + setonlylocal(&ll, "LOGNAME", pw->pw_name); + gethostname(toybuf, sizeof(toybuf)-1); + *ll++ = xmprintf("HOSTNAME=%s", toybuf); + uname(&uu); + setonlylocal(&ll, "HOSTTYPE", uu.machine); + sprintf(toybuf, "%s-unknown-linux", uu.machine); + setonlylocal(&ll, "MACHTYPE", toybuf); + setonlylocal(&ll, "OSTYPE", uu.sysname); + // sprintf(toybuf, "%s-toybox", TOYBOX_VERSION); + // setonlylocal(&ll, "BASH_VERSION", toybuf); + *ll++ = xstrdup("OPTERR=1"); + *toybuf = 0; + if (readlink0("/proc/self/exe", toybuf, sizeof(toybuf))) + setonlylocal(&ll, "BASH", toybuf); + *ll = 0; // Ensure environ copied and toys.envc set, and clean out illegal entries xunsetenv(""); @@ -1875,12 +1882,30 @@ void subshell_imports(void) } environ[toys.optc = to] = 0; + // set/update PWD + sh_run("cd ."); + + // set _ to path to this shell + s = toys.argv[0]; + ss = 0; + if (!strchr(s, '/')) { + if (!(ss = getcwd(0, 0))) { + if (*toybuf) s = toybuf; + } else { + s = xmprintf("%s/%s", ss, s); + free(ss); + ss = s; + } + } + xsetenv("_", s); + free(ss); + if (!getvar("SHLVL")) xsetenv("SHLVL", "1"); + //TODO indexed array,associative array,integer,local,nameref,readonly,uppercase // if (s+1pw_dir)?pw->pw_dir:"/"), TAKE_MEM); - } - sh_run("cd ."); - if (BUGBUG) { int fd = open("/dev/tty", O_RDWR); dup2(fd, 255); close(fd); } // Is this an interactive shell? // if (FLAG(i) || (!FLAG(c)&&(FLAG(S)||!toys.optc) && isatty(0) && isatty(1))) @@ -1930,10 +1942,12 @@ if (BUGBUG) { int fd = open("/dev/tty", O_RDWR); dup2(fd, 255); close(fd); } // Set up signal handlers and grab control of this tty. // Read environment for exports from parent shell - subshell_imports(); + subshell_setup(); memset(&scratch, 0, sizeof(scratch)); - if (TT.command) f = fmemopen(TT.command, strlen(TT.command), "r"); + +// TODO unify fmemopen() here with sh_run + if (TT.c) f = fmemopen(TT.c, strlen(TT.c), "r"); else if (*toys.optargs) f = xfopen(*toys.optargs, "r"); else { f = stdin; @@ -1949,7 +1963,7 @@ if (BUGBUG) { int fd = open("/dev/tty", O_RDWR); dup2(fd, 255); close(fd); } if (!s) s = prompt ? "> " : (getpid() ? "\\$ " : "# "); do_prompt(s); } else TT.lineno++; -// TODO line editing/history +// TODO line editing/history, should set $COLUMNS $LINES and sigwinch update if (!(new = xgetline(f ? f : stdin, 0))) break; // TODO if (!isspace(*new)) add_to_history(line); @@ -2035,7 +2049,7 @@ void cd_main(void) if (bad || chdir(dd)) perror_msg("chdir '%s'", dd); else { - if (pwd) xsetenv("OLD", pwd); + if (pwd) xsetenv("OLDPWD", pwd); xsetenv("PWD", dd); } free(dd); -- cgit v1.2.3