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..2f7eadd --- /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. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 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/param.h> +#include <sys/types.h> +#include <errno.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> +#include <stdio.h> +#include <paths.h> + +#if __STDC__ +#include <stdarg.h> +#else +#include <varargs.h> +#endif + +extern char **environ; + +static char ** +buildargv(ap, arg, envpp) + va_list ap; + const char *arg; + char ***envpp; +{ + static int memsize; + static char **argv; + register int off; + + argv = NULL; + for (off = 0;; ++off) { + if (off >= memsize) { + memsize += 50; /* Starts out at 0. */ + memsize *= 2; /* Ramp up fast. */ + if (!(argv = realloc(argv, memsize * sizeof(char *)))) { + memsize = 0; + return (NULL); + } + if (off == 0) { + argv[0] = (char *)arg; + off = 1; + } + } + if (!(argv[off] = va_arg(ap, char *))) + break; + } + /* Get environment pointer if user supposed to provide one. */ + if (envpp) + *envpp = va_arg(ap, char **); + return (argv); +} + +int +#if __STDC__ +execl(const char *name, const char *arg, ...) +#else +execl(name, arg, va_alist) + const char *name; + const char *arg; + va_dcl +#endif +{ + va_list ap; + int sverrno; + char **argv; + +#if __STDC__ + va_start(ap, arg); +#else + va_start(ap); +#endif + if (argv = buildargv(ap, arg, NULL)) + (void)execve(name, argv, environ); + va_end(ap); + sverrno = errno; + free(argv); + errno = sverrno; + return (-1); +} + +int +#if __STDC__ +execle(const char *name, const char *arg, ...) +#else +execle(name, arg, va_alist) + const char *name; + const char *arg; + va_dcl +#endif +{ + va_list ap; + int sverrno; + char **argv, **envp; + +#if __STDC__ + va_start(ap, arg); +#else + va_start(ap); +#endif + if (argv = buildargv(ap, arg, &envp)) + (void)execve(name, argv, envp); + va_end(ap); + sverrno = errno; + free(argv); + errno = sverrno; + return (-1); +} + +int +#if __STDC__ +execlp(const char *name, const char *arg, ...) +#else +execlp(name, arg, va_alist) + const char *name; + const char *arg; + va_dcl +#endif +{ + va_list ap; + int sverrno; + char **argv; + +#if __STDC__ + va_start(ap, arg); +#else + va_start(ap); +#endif + if (argv = buildargv(ap, arg, NULL)) + (void)execvp(name, argv); + va_end(ap); + sverrno = errno; + free(argv); + errno = sverrno; + return (-1); +} + +int +execv(name, argv) + const char *name; + char * const *argv; +{ + (void)execve(name, argv, environ); + return (-1); +} + +int +execvp(name, argv) + const char *name; + char * const *argv; +{ + static int memsize; + static char **memp; + register int cnt, lp, ln; + register char *p; + int eacces, etxtbsy; + char *bp, *cur, *path, buf[MAXPATHLEN]; + + /* If it's an absolute or relative path name, it's easy. */ + if (index(name, '/')) { + bp = (char *)name; + cur = path = NULL; + goto retry; + } + bp = buf; + + /* Get the path we're searching. */ + if (!(path = getenv("PATH"))) + path = _PATH_DEFPATH; + cur = path = strdup(path); + + eacces = etxtbsy = 0; + while (p = strsep(&cur, ":")) { + /* + * It's a SHELL path -- double, leading and trailing colons + * mean the current directory. + */ + if (!*p) { + 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 EACCES: + eacces = 1; + break; + case ENOENT: + break; + case ENOEXEC: + for (cnt = 0; argv[cnt]; ++cnt); + if ((cnt + 2) * sizeof(char *) > memsize) { + memsize = (cnt + 2) * sizeof(char *); + if ((memp = realloc(memp, memsize)) == NULL) { + memsize = 0; + 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 ETXTBSY: + if (etxtbsy < 3) + (void)sleep(++etxtbsy); + goto retry; + default: + goto done; + } + } + if (eacces) + errno = EACCES; + else if (!errno) + errno = ENOENT; +done: if (path) + free(path); + return (-1); +} |
