diff options
Diffstat (limited to 'lib/libc/gen/exec.c')
| -rw-r--r-- | lib/libc/gen/exec.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/lib/libc/gen/exec.c b/lib/libc/gen/exec.c new file mode 100644 index 0000000..2cf7a36 --- /dev/null +++ b/lib/libc/gen/exec.c @@ -0,0 +1,271 @@ +/*- + * Copyright (c) 1991, 1993 + * The Regents of the University of California. All rights reserved. + * + * 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. + * 4. 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. + */ + +#if defined(LIBC_SCCS) && !defined(lint) +static char sccsid[] = "@(#)exec.c 8.1 (Berkeley) 6/4/93"; +#endif /* LIBC_SCCS and not lint */ +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include "namespace.h" +#include <sys/param.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <errno.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> +#include <stdio.h> +#include <paths.h> + +#include <stdarg.h> +#include "un-namespace.h" + +extern char **environ; + +int +execl(const char *name, const char *arg, ...) +{ + va_list ap; + char **argv; + int n; + + va_start(ap, arg); + n = 1; + while (va_arg(ap, char *) != NULL) + n++; + va_end(ap); + argv = alloca((n + 1) * sizeof(*argv)); + if (argv == NULL) { + errno = ENOMEM; + return (-1); + } + va_start(ap, arg); + n = 1; + argv[0] = (char *)arg; + while ((argv[n] = va_arg(ap, char *)) != NULL) + n++; + va_end(ap); + return (_execve(name, argv, environ)); +} + +int +execle(const char *name, const char *arg, ...) +{ + va_list ap; + char **argv, **envp; + int n; + + va_start(ap, arg); + n = 1; + while (va_arg(ap, char *) != NULL) + n++; + va_end(ap); + argv = alloca((n + 1) * sizeof(*argv)); + if (argv == NULL) { + errno = ENOMEM; + return (-1); + } + va_start(ap, arg); + n = 1; + argv[0] = (char *)arg; + while ((argv[n] = va_arg(ap, char *)) != NULL) + n++; + envp = va_arg(ap, char **); + va_end(ap); + return (_execve(name, argv, envp)); +} + +int +execlp(const char *name, const char *arg, ...) +{ + va_list ap; + char **argv; + int n; + + va_start(ap, arg); + n = 1; + while (va_arg(ap, char *) != NULL) + n++; + va_end(ap); + argv = alloca((n + 1) * sizeof(*argv)); + if (argv == NULL) { + errno = ENOMEM; + return (-1); + } + va_start(ap, arg); + n = 1; + argv[0] = (char *)arg; + while ((argv[n] = va_arg(ap, char *)) != NULL) + n++; + va_end(ap); + return (execvp(name, argv)); +} + +int +execv(name, argv) + const char *name; + char * const *argv; +{ + (void)_execve(name, argv, environ); + return (-1); +} + +int +execvp(const char *name, char * const *argv) +{ + const char *path; + + /* Get the path we're searching. */ + if ((path = getenv("PATH")) == NULL) + path = _PATH_DEFPATH; + + return (execvP(name, path, argv)); +} + +int +execvP(name, path, argv) + const char *name; + const char *path; + char * const *argv; +{ + char **memp; + int cnt, lp, ln; + char *p; + int eacces, save_errno; + char *bp, *cur, buf[MAXPATHLEN]; + struct stat sb; + + eacces = 0; + + /* If it's an absolute or relative path name, it's easy. */ + if (index(name, '/')) { + bp = (char *)name; + cur = NULL; + goto retry; + } + bp = buf; + + /* If it's an empty path name, fail in the usual POSIX way. */ + if (*name == '\0') { + errno = ENOENT; + return (-1); + } + + cur = alloca(strlen(path) + 1); + if (cur == NULL) { + errno = ENOMEM; + return (-1); + } + strcpy(cur, path); + while ((p = strsep(&cur, ":")) != NULL) { + /* + * It's a SHELL path -- double, leading and trailing colons + * mean the current directory. + */ + if (*p == '\0') { + p = "."; + lp = 1; + } else + lp = strlen(p); + ln = strlen(name); + + /* + * If the path is too long complain. This is a possible + * security issue; given a way to make the path too long + * the user may execute the wrong program. + */ + if (lp + ln + 2 > sizeof(buf)) { + (void)_write(STDERR_FILENO, "execvP: ", 8); + (void)_write(STDERR_FILENO, p, lp); + (void)_write(STDERR_FILENO, ": path too long\n", + 16); + continue; + } + bcopy(p, buf, lp); + buf[lp] = '/'; + bcopy(name, buf + lp + 1, ln); + buf[lp + ln + 1] = '\0'; + +retry: (void)_execve(bp, argv, environ); + switch (errno) { + case E2BIG: + goto done; + case ELOOP: + case ENAMETOOLONG: + case ENOENT: + break; + case ENOEXEC: + for (cnt = 0; argv[cnt]; ++cnt) + ; + memp = alloca((cnt + 2) * sizeof(char *)); + if (memp == NULL) { + /* errno = ENOMEM; XXX override ENOEXEC? */ + goto done; + } + memp[0] = "sh"; + memp[1] = bp; + bcopy(argv + 1, memp + 2, cnt * sizeof(char *)); + (void)_execve(_PATH_BSHELL, memp, environ); + goto done; + case ENOMEM: + goto done; + case ENOTDIR: + break; + case ETXTBSY: + /* + * We used to retry here, but sh(1) doesn't. + */ + goto done; + default: + /* + * EACCES may be for an inaccessible directory or + * a non-executable file. Call stat() to decide + * which. This also handles ambiguities for EFAULT + * and EIO, and undocumented errors like ESTALE. + * We hope that the race for a stat() is unimportant. + */ + save_errno = errno; + if (stat(bp, &sb) != 0) + break; + if (save_errno == EACCES) { + eacces = 1; + continue; + } + errno = save_errno; + goto done; + } + } + if (eacces) + errno = EACCES; + else + errno = ENOENT; +done: + return (-1); +} |
