| 0,0 → 1,225 |
|---|
| /* Copyright (c) 2008, Tim Post <tinkertim@gmail.com> |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are met: |
| * |
| * Redistributions of source code must retain the above copyright notice, this |
| * list of conditions and the following disclaimer. |
| * |
| * 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. |
| * |
| * Neither the name of the original program's authors 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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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. |
| */ |
| |
| /* The VERY basics of execute in place support. These are buggy, leaky |
| * and not nearly done. Only here for beta testing!! You were warned!! |
| * TODO: |
| * Hash command lookups to save time |
| * Create a running pointer to **path and advance/rewind it as we go */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <string.h> |
| #include <fcntl.h> |
| |
| #ifndef HELENOS |
| #include <linux/limits.h> |
| #include <sys/errno.h> |
| #include <sys/wait.h> |
| #endif |
| |
| #include "config.h" |
| #include "util.h" |
| #include "exec.h" |
| #include "errors.h" |
| |
| /* Easiest way to handle a shared + allocated string, a structure with |
| * one member is sort of silly :) */ |
| char *found; |
| |
| /* work-around for access() */ |
| unsigned int try_access(const char *f) |
| { |
| int fd; |
| |
| fd = open(f, O_RDONLY); |
| if (fd > 0) { |
| close(fd); |
| return 1; |
| } else |
| return 0; |
| } |
| |
| /* Returns the full path of "cmd" if cmd is found, else just hand back |
| * cmd as it was presented */ |
| char *find_command(char *cmd) |
| { |
| char *path_orig, *path_tok; |
| char *path[PATH_MAX]; |
| int rc, n = 0, i = 0; |
| size_t x = strlen(cmd) + 2; |
| |
| found = (char *)malloc(PATH_MAX); |
| |
| /* The user has specified the full path, just give it back. Don't test it, |
| * they seem to know what they're doing. */ |
| if (cmd[0] == '/' || cmd [0] == '.') |
| return (char *)cmd; |
| |
| #ifdef HELENOS |
| path_orig = PATH; |
| #else |
| path_orig = getenv("PATH"); |
| if (NULL == path_orig) |
| path_orig = PATH; |
| #endif |
| |
| path_tok = cli_strdup(path_orig); |
| |
| /* Extract the PATH env to a path[] array */ |
| path[n] = cli_strtok(path_tok, PATH_DELIM); |
| while (NULL != path[n]) { |
| if ((strlen(path[n]) + x ) > PATH_MAX) { |
| cli_error(CL_ENOTSUP, |
| "Segment %d of path is too large, search ends at segment %d", |
| n, n-1); |
| break; |
| } |
| path[++n] = cli_strtok(NULL, PATH_DELIM); |
| } |
| |
| /* We now have n places to look for the command */ |
| for (i=0; path[i]; i++) { |
| memset(found, 0, sizeof(found)); |
| snprintf(found, PATH_MAX, "%s/%s", path[i], cmd); |
| #ifdef HELENOS |
| rc = try_access(found); |
| #else |
| rc = access(found, F_OK); |
| #endif |
| if (rc >= 0) { |
| /* We found it */ |
| free(path_tok); |
| return (char *) found; |
| } |
| } |
| |
| /* We didn't find it, just give it back as-is. Could be an alias |
| * set in the parent shell */ |
| free(path_tok); |
| return (char *) cmd; |
| } |
| |
| #ifdef HELENOS |
| task_id_t try_exec(char *cmd, char **argv) |
| { |
| task_id_t tid; |
| char *tmp; |
| |
| tmp = cli_strdup(find_command(cmd)); |
| free(found); |
| |
| tid = task_spawn((const char *)tmp, (const char **)argv); |
| free(tmp); |
| |
| if (tid == 0) |
| /* HelenOS does not set errno, so all we can do is report |
| * a task ID of 0 as a generic failure. */ |
| cli_error(CL_EEXEC, "Can not spawn %s", cmd); |
| |
| return tid; |
| } |
| |
| #else |
| int try_exec(char *cmd, char **argv) |
| { |
| char *tmp; |
| pid_t pid; |
| int status; |
| |
| /* Copy the result of allocated 'found' */ |
| tmp = cli_strdup(find_command(cmd)); |
| /* free the pointer, no longer needed */ |
| free(found); |
| |
| if (-1 == (access(tmp, F_OK))) { |
| cli_error(CL_EFAIL, |
| "%s : No such external, modular or builtin command", tmp); |
| free(tmp); |
| return CL_EFAIL; |
| } |
| |
| /* Create a child to run the program */ |
| pid = fork(); |
| if (pid == 0) { |
| execv(tmp, argv); |
| exit(errno); |
| } else if (pid > 0) { |
| /* Block until we get a PID (and result) */ |
| wait(&status); |
| status = status / 256; |
| } else { |
| /* Could not fork, ulimit or out of memory */ |
| cli_error(CL_ENOMEM, "Could not fork"); |
| free(tmp); |
| return CL_ENOMEM; |
| } |
| |
| free(tmp); |
| |
| /* No need to go any further if status == 0 */ |
| /* |
| if (status == 0) |
| return status; |
| */ |
| /* Decode any errors from execv() (these explain themselves) */ |
| switch (status) { |
| case ENOTDIR: |
| cli_error(CL_EFAIL, "%s : No such file or directory", tmp); |
| status = CL_EFAIL; |
| break; |
| case EISDIR: |
| cli_error(CL_EFAIL, "%s : Command is a directory", tmp); |
| status = CL_EFAIL; |
| break; |
| case EACCES: |
| cli_error(CL_EPERM, "%s :", tmp); |
| status = CL_EFAIL; |
| break; |
| case ENOMEM: |
| cli_error(CL_ENOMEM, "%s :", tmp); |
| status = CL_EFAIL; |
| break; |
| case ENAMETOOLONG: |
| cli_error(CL_EFAIL, "Argument list too long"); |
| status = CL_EFAIL; |
| break; |
| case EFAULT: |
| cli_error(CL_EFAIL, "Invalid argument pointer\n(please report " |
| "this to %s)", PACKAGE_BUGREPORT); |
| status = CL_EFAIL; |
| break; |
| } |
| |
| return status; |
| } |
| |
| #endif /* HELENOS */ |