diff options
Diffstat (limited to 'bin/1sh/exec.c')
| -rw-r--r-- | bin/1sh/exec.c | 784 |
1 files changed, 0 insertions, 784 deletions
diff --git a/bin/1sh/exec.c b/bin/1sh/exec.c deleted file mode 100644 index 81efa565..00000000 --- a/bin/1sh/exec.c +++ /dev/null @@ -1,784 +0,0 @@ -/*- - * Copyright (c) 1991, 1993 - * The Regents of the University of California. All rights reserved. - * - * This code is derived from software contributed to Berkeley by - * Kenneth Almquist. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#ifndef lint -#if 0 -static char sccsid[] = "@(#)exec.c 8.4 (Berkeley) 6/8/95"; -#endif -#endif /* not lint */ -#include <sys/cdefs.h> -/* $FreeBSD: releng/12.1/bin/sh/exec.c 336320 2018-07-15 21:55:17Z jilles $ */ - -#include <sys/types.h> -#include <sys/stat.h> -#include <unistd.h> -#include <fcntl.h> -#include <errno.h> -#include <paths.h> -#include <stdlib.h> - -/* - * When commands are first encountered, they are entered in a hash table. - * This ensures that a full path search will not have to be done for them - * on each invocation. - * - * We should investigate converting to a linear search, even though that - * would make the command name "hash" a misnomer. - */ - -#include "shell.h" -#include "main.h" -#include "nodes.h" -#include "parser.h" -#include "redir.h" -#include "eval.h" -#include "exec.h" -#include "builtins.h" -#include "var.h" -#include "options.h" -#include "input.h" -#include "output.h" -#include "syntax.h" -#include "memalloc.h" -#include "error.h" -#include "mystring.h" -#include "show.h" -#include "jobs.h" -#include "alias.h" - - -#define CMDTABLESIZE 31 /* should be prime */ - - - -struct tblentry { - struct tblentry *next; /* next entry in hash chain */ - union param param; /* definition of builtin function */ - int special; /* flag for special builtin commands */ - signed char cmdtype; /* index identifying command */ - char cmdname[]; /* name of command */ -}; - - -static struct tblentry *cmdtable[CMDTABLESIZE]; -static int cmdtable_cd = 0; /* cmdtable contains cd-dependent entries */ -int exerrno = 0; /* Last exec error */ - - -static void tryexec(char *, char **, char **); -static void printentry(struct tblentry *, int); -static struct tblentry *cmdlookup(const char *, int); -static void delete_cmd_entry(void); -static void addcmdentry(const char *, struct cmdentry *); - - - -/* - * Exec a program. Never returns. If you change this routine, you may - * have to change the find_command routine as well. - * - * The argv array may be changed and element argv[-1] should be writable. - */ - -void -shellexec(char **argv, char **envp, const char *path, int idx) -{ - char *cmdname; - const char *opt; - int e; - - if (strchr(argv[0], '/') != NULL) { - tryexec(argv[0], argv, envp); - e = errno; - } else { - e = ENOENT; - while ((cmdname = padvance(&path, &opt, argv[0])) != NULL) { - if (--idx < 0 && opt == NULL) { - tryexec(cmdname, argv, envp); - if (errno != ENOENT && errno != ENOTDIR) - e = errno; - if (e == ENOEXEC) - break; - } - stunalloc(cmdname); - } - } - - /* Map to POSIX errors */ - if (e == ENOENT || e == ENOTDIR) { - exerrno = 127; - exerror(EXEXEC, "%s: not found", argv[0]); - } else { - exerrno = 126; - exerror(EXEXEC, "%s: %s", argv[0], strerror(e)); - } -} - - -static void -tryexec(char *cmd, char **argv, char **envp) -{ - int e, in; - ssize_t n; - char buf[256]; - - execve(cmd, argv, envp); - e = errno; - if (e == ENOEXEC) { - INTOFF; - in = open(cmd, O_RDONLY | O_NONBLOCK); - if (in != -1) { - n = pread(in, buf, sizeof buf, 0); - close(in); - if (n > 0 && memchr(buf, '\0', n) != NULL) { - errno = ENOEXEC; - return; - } - } - *argv = cmd; - *--argv = (char *)(_PATH_BSHELL); - execve(_PATH_BSHELL, argv, envp); - } - errno = e; -} - -/* - * Do a path search. The variable path (passed by reference) should be - * set to the start of the path before the first call; padvance will update - * this value as it proceeds. Successive calls to padvance will return - * the possible path expansions in sequence. If popt is not NULL, options - * are processed: if an option (indicated by a percent sign) appears in - * the path entry then *popt will be set to point to it; else *popt will be - * set to NULL. If popt is NULL, percent signs are not special. - */ - -char * -padvance(const char **path, const char **popt, const char *name) -{ - const char *p, *start; - char *q; - size_t len, namelen; - - if (*path == NULL) - return NULL; - start = *path; - if (popt != NULL) - for (p = start; *p && *p != ':' && *p != '%'; p++) - ; /* nothing */ - else - for (p = start; *p && *p != ':'; p++) - ; /* nothing */ - namelen = strlen(name); - len = p - start + namelen + 2; /* "2" is for '/' and '\0' */ - STARTSTACKSTR(q); - CHECKSTRSPACE(len, q); - if (p != start) { - memcpy(q, start, p - start); - q += p - start; - *q++ = '/'; - } - memcpy(q, name, namelen + 1); - if (popt != NULL) { - if (*p == '%') { - *popt = ++p; - while (*p && *p != ':') p++; - } else - *popt = NULL; - } - if (*p == ':') - *path = p + 1; - else - *path = NULL; - return stalloc(len); -} - - - -/*** Command hashing code ***/ - - -int -hashcmd(int argc __unused, char **argv __unused) -{ - struct tblentry **pp; - struct tblentry *cmdp; - int c; - int verbose; - struct cmdentry entry; - char *name; - int errors; - - errors = 0; - verbose = 0; - while ((c = nextopt("rv")) != '\0') { - if (c == 'r') { - clearcmdentry(); - } else if (c == 'v') { - verbose++; - } - } - if (*argptr == NULL) { - for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) { - for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) { - if (cmdp->cmdtype == CMDNORMAL) - printentry(cmdp, verbose); - } - } - return 0; - } - while ((name = *argptr) != NULL) { - if ((cmdp = cmdlookup(name, 0)) != NULL - && cmdp->cmdtype == CMDNORMAL) - delete_cmd_entry(); - find_command(name, &entry, DO_ERR, pathval()); - if (entry.cmdtype == CMDUNKNOWN) - errors = 1; - else if (verbose) { - cmdp = cmdlookup(name, 0); - if (cmdp != NULL) - printentry(cmdp, verbose); - else { - outfmt(out2, "%s: not found\n", name); - errors = 1; - } - flushall(); - } - argptr++; - } - return errors; -} - - -static void -printentry(struct tblentry *cmdp, int verbose) -{ - int idx; - const char *path, *opt; - char *name; - - if (cmdp->cmdtype == CMDNORMAL) { - idx = cmdp->param.index; - path = pathval(); - do { - name = padvance(&path, &opt, cmdp->cmdname); - stunalloc(name); - } while (--idx >= 0); - out1str(name); - } else if (cmdp->cmdtype == CMDBUILTIN) { - out1fmt("builtin %s", cmdp->cmdname); - } else if (cmdp->cmdtype == CMDFUNCTION) { - out1fmt("function %s", cmdp->cmdname); - if (verbose) { - INTOFF; - name = commandtext(getfuncnode(cmdp->param.func)); - out1c(' '); - out1str(name); - ckfree(name); - INTON; - } -#ifdef DEBUG - } else { - error("internal error: cmdtype %d", cmdp->cmdtype); -#endif - } - out1c('\n'); -} - - - -/* - * Resolve a command name. If you change this routine, you may have to - * change the shellexec routine as well. - */ - -void -find_command(const char *name, struct cmdentry *entry, int act, - const char *path) -{ - struct tblentry *cmdp, loc_cmd; - int idx; - const char *opt; - char *fullname; - struct stat statb; - int e; - int i; - int spec; - int cd; - - /* If name contains a slash, don't use the hash table */ - if (strchr(name, '/') != NULL) { - entry->cmdtype = CMDNORMAL; - entry->u.index = 0; - entry->special = 0; - return; - } - - cd = 0; - - /* If name is in the table, we're done */ - if ((cmdp = cmdlookup(name, 0)) != NULL) { - if (cmdp->cmdtype == CMDFUNCTION && act & DO_NOFUNC) - cmdp = NULL; - else - goto success; - } - - /* Check for builtin next */ - if ((i = find_builtin(name, &spec)) >= 0) { - INTOFF; - cmdp = cmdlookup(name, 1); - if (cmdp->cmdtype == CMDFUNCTION) - cmdp = &loc_cmd; - cmdp->cmdtype = CMDBUILTIN; - cmdp->param.index = i; - cmdp->special = spec; - INTON; - goto success; - } - - /* We have to search path. */ - - e = ENOENT; - idx = -1; - for (;(fullname = padvance(&path, &opt, name)) != NULL; - stunalloc(fullname)) { - idx++; - if (opt) { - if (strncmp(opt, "func", 4) == 0) { - /* handled below */ - } else { - continue; /* ignore unimplemented options */ - } - } - if (fullname[0] != '/') - cd = 1; - if (stat(fullname, &statb) < 0) { - if (errno != ENOENT && errno != ENOTDIR) - e = errno; - continue; - } - e = EACCES; /* if we fail, this will be the error */ - if (!S_ISREG(statb.st_mode)) - continue; - if (opt) { /* this is a %func directory */ - readcmdfile(fullname); - if ((cmdp = cmdlookup(name, 0)) == NULL || cmdp->cmdtype != CMDFUNCTION) - error("%s not defined in %s", name, fullname); - stunalloc(fullname); - goto success; - } -#ifdef notdef - if (statb.st_uid == geteuid()) { - if ((statb.st_mode & 0100) == 0) - goto loop; - } else if (statb.st_gid == getegid()) { - if ((statb.st_mode & 010) == 0) - goto loop; - } else { - if ((statb.st_mode & 01) == 0) - goto loop; - } -#endif - TRACE(("searchexec \"%s\" returns \"%s\"\n", name, fullname)); - INTOFF; - stunalloc(fullname); - cmdp = cmdlookup(name, 1); - if (cmdp->cmdtype == CMDFUNCTION) - cmdp = &loc_cmd; - cmdp->cmdtype = CMDNORMAL; - cmdp->param.index = idx; - cmdp->special = 0; - INTON; - goto success; - } - - if (act & DO_ERR) { - if (e == ENOENT || e == ENOTDIR) - outfmt(out2, "%s: not found\n", name); - else - outfmt(out2, "%s: %s\n", name, strerror(e)); - } - entry->cmdtype = CMDUNKNOWN; - entry->u.index = 0; - entry->special = 0; - return; - -success: - if (cd) - cmdtable_cd = 1; - entry->cmdtype = cmdp->cmdtype; - entry->u = cmdp->param; - entry->special = cmdp->special; -} - - - -/* - * Search the table of builtin commands. - */ - -int -find_builtin(const char *name, int *special) -{ - const unsigned char *bp; - size_t len; - - len = strlen(name); - for (bp = builtincmd ; *bp ; bp += 2 + bp[0]) { - if (bp[0] == len && memcmp(bp + 2, name, len) == 0) { - *special = (bp[1] & BUILTIN_SPECIAL) != 0; - return bp[1] & ~BUILTIN_SPECIAL; - } - } - return -1; -} - - - -/* - * Called when a cd is done. If any entry in cmdtable depends on the current - * directory, simply clear cmdtable completely. - */ - -void -hashcd(void) -{ - if (cmdtable_cd) - clearcmdentry(); -} - - - -/* - * Called before PATH is changed. The argument is the new value of PATH; - * pathval() still returns the old value at this point. Called with - * interrupts off. - */ - -void -changepath(const char *newval __unused) -{ - clearcmdentry(); -} - - -/* - * Clear out cached utility locations. - */ - -void -clearcmdentry(void) -{ - struct tblentry **tblp; - struct tblentry **pp; - struct tblentry *cmdp; - - INTOFF; - for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) { - pp = tblp; - while ((cmdp = *pp) != NULL) { - if (cmdp->cmdtype == CMDNORMAL) { - *pp = cmdp->next; - ckfree(cmdp); - } else { - pp = &cmdp->next; - } - } - } - cmdtable_cd = 0; - INTON; -} - - -/* - * Locate a command in the command hash table. If "add" is nonzero, - * add the command to the table if it is not already present. The - * variable "lastcmdentry" is set to point to the address of the link - * pointing to the entry, so that delete_cmd_entry can delete the - * entry. - */ - -static struct tblentry **lastcmdentry; - - -static struct tblentry * -cmdlookup(const char *name, int add) -{ - unsigned int hashval; - const char *p; - struct tblentry *cmdp; - struct tblentry **pp; - size_t len; - - p = name; - hashval = (unsigned char)*p << 4; - while (*p) - hashval += *p++; - pp = &cmdtable[hashval % CMDTABLESIZE]; - for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) { - if (equal(cmdp->cmdname, name)) - break; - pp = &cmdp->next; - } - if (add && cmdp == NULL) { - INTOFF; - len = strlen(name); - cmdp = *pp = ckmalloc(sizeof (struct tblentry) + len + 1); - cmdp->next = NULL; - cmdp->cmdtype = CMDUNKNOWN; - memcpy(cmdp->cmdname, name, len + 1); - INTON; - } - lastcmdentry = pp; - return cmdp; -} - -/* - * Delete the command entry returned on the last lookup. - */ - -static void -delete_cmd_entry(void) -{ - struct tblentry *cmdp; - - INTOFF; - cmdp = *lastcmdentry; - *lastcmdentry = cmdp->next; - ckfree(cmdp); - INTON; -} - - - -/* - * Add a new command entry, replacing any existing command entry for - * the same name. - */ - -static void -addcmdentry(const char *name, struct cmdentry *entry) -{ - struct tblentry *cmdp; - - INTOFF; - cmdp = cmdlookup(name, 1); - if (cmdp->cmdtype == CMDFUNCTION) { - unreffunc(cmdp->param.func); - } - cmdp->cmdtype = entry->cmdtype; - cmdp->param = entry->u; - cmdp->special = entry->special; - INTON; -} - - -/* - * Define a shell function. - */ - -void -defun(const char *name, union node *func) -{ - struct cmdentry entry; - - INTOFF; - entry.cmdtype = CMDFUNCTION; - entry.u.func = copyfunc(func); - entry.special = 0; - addcmdentry(name, &entry); - INTON; -} - - -/* - * Delete a function if it exists. - * Called with interrupts off. - */ - -int -unsetfunc(const char *name) -{ - struct tblentry *cmdp; - - if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->cmdtype == CMDFUNCTION) { - unreffunc(cmdp->param.func); - delete_cmd_entry(); - return (0); - } - return (0); -} - - -/* - * Check if a function by a certain name exists. - */ -int -isfunc(const char *name) -{ - struct tblentry *cmdp; - cmdp = cmdlookup(name, 0); - return (cmdp != NULL && cmdp->cmdtype == CMDFUNCTION); -} - - -/* - * Shared code for the following builtin commands: - * type, command -v, command -V - */ - -int -typecmd_impl(int argc, char **argv, int cmd, const char *path) -{ - struct cmdentry entry; - struct tblentry *cmdp; - const char *const *pp; - struct alias *ap; - int i; - int error1 = 0; - - if (path != pathval()) - clearcmdentry(); - - for (i = 1; i < argc; i++) { - /* First look at the keywords */ - for (pp = parsekwd; *pp; pp++) - if (**pp == *argv[i] && equal(*pp, argv[i])) - break; - - if (*pp) { - if (cmd == TYPECMD_SMALLV) - out1fmt("%s\n", argv[i]); - else - out1fmt("%s is a shell keyword\n", argv[i]); - continue; - } - - /* Then look at the aliases */ - if ((ap = lookupalias(argv[i], 1)) != NULL) { - if (cmd == TYPECMD_SMALLV) { - out1fmt("alias %s=", argv[i]); - out1qstr(ap->val); - outcslow('\n', out1); - } else - out1fmt("%s is an alias for %s\n", argv[i], - ap->val); - continue; - } - - /* Then check if it is a tracked alias */ - if ((cmdp = cmdlookup(argv[i], 0)) != NULL) { - entry.cmdtype = cmdp->cmdtype; - entry.u = cmdp->param; - entry.special = cmdp->special; - } - else { - /* Finally use brute force */ - find_command(argv[i], &entry, 0, path); - } - - switch (entry.cmdtype) { - case CMDNORMAL: { - if (strchr(argv[i], '/') == NULL) { - const char *path2 = path; - const char *opt2; - char *name; - int j = entry.u.index; - do { - name = padvance(&path2, &opt2, argv[i]); - stunalloc(name); - } while (--j >= 0); - if (cmd == TYPECMD_SMALLV) - out1fmt("%s\n", name); - else - out1fmt("%s is%s %s\n", argv[i], - (cmdp && cmd == TYPECMD_TYPE) ? - " a tracked alias for" : "", - name); - } else { - if (faccessat(AT_FDCWD, argv[i], X_OK, AT_EACCESS) == 0) { - if (cmd == TYPECMD_SMALLV) - out1fmt("%s\n", argv[i]); - else - out1fmt("%s is %s\n", argv[i], - argv[i]); - } else { - if (cmd != TYPECMD_SMALLV) - outfmt(out2, "%s: %s\n", - argv[i], strerror(errno)); - error1 |= 127; - } - } - break; - } - case CMDFUNCTION: - if (cmd == TYPECMD_SMALLV) - out1fmt("%s\n", argv[i]); - else - out1fmt("%s is a shell function\n", argv[i]); - break; - - case CMDBUILTIN: - if (cmd == TYPECMD_SMALLV) - out1fmt("%s\n", argv[i]); - else if (entry.special) - out1fmt("%s is a special shell builtin\n", - argv[i]); - else - out1fmt("%s is a shell builtin\n", argv[i]); - break; - - default: - if (cmd != TYPECMD_SMALLV) - outfmt(out2, "%s: not found\n", argv[i]); - error1 |= 127; - break; - } - } - - if (path != pathval()) - clearcmdentry(); - - return error1; -} - -/* - * Locate and print what a word is... - */ - -int -typecmd(int argc, char **argv) -{ - if (argc > 2 && strcmp(argv[1], "--") == 0) - argc--, argv++; - return typecmd_impl(argc, argv, TYPECMD_TYPE, bltinlookup("PATH", 1)); -} |