uspace/app/redir/redir.c

   1 /*
   2  * Copyright (c) 2009 Martin Decky
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  *   notice, this list of conditions and the following disclaimer.
  11  * - Redistributions in binary form must reproduce the above copyright
  12  *   notice, this list of conditions and the following disclaimer in the
  13  *   documentation and/or other materials provided with the distribution.
  14  * - The name of the author may not be used to endorse or promote products
  15  *   derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 /** @addtogroup redir Redirector
  30  * @brief Redirect stdin/stdout/stderr.
  31  * @{
  32  */
  33 /**
  34  * @file
  35  */
  36
  37 #include <sys/types.h>
  38 #include <stdlib.h>
  39 #include <fcntl.h>
  40 #include <unistd.h>
  41 #include <str.h>
  42 #include <stdio.h>
  43 #include <task.h>
  44 #include <str_error.h>
  45 #include <errno.h>
  46
  47 #define NAME  "redir"
  48
  49 static void usage(void)
  50 {
  51         fprintf(stderr, "Usage: %s [-i <stdin>] [-o <stdout>] [-e <stderr>] -- <cmd> [args ...]\n",
  52             NAME);
  53 }
  54
  55 static void reopen(FILE **stream, int fd, const char *path, int flags, const char *mode)
  56 {
  57         if (fclose(*stream))
  58                 return;
  59
  60         *stream = NULL;
  61
  62         int oldfd = open(path, flags);
  63         if (oldfd < 0)
  64                 return;
  65
  66         if (oldfd != fd) {
  67                 if (dup2(oldfd, fd) != fd)
  68                         return;
  69
  70                 if (close(oldfd))
  71                         return;
  72         }
  73
  74         *stream = fdopen(fd, mode);
  75 }
  76
  77 static task_id_t spawn(int argc, char *argv[])
  78 {
  79         const char **args;
  80         task_id_t id = 0;
  81         int rc;
  82
  83         args = (const char **) calloc(argc + 1, sizeof(char *));
  84         if (!args) {
  85                 fprintf(stderr, "No memory available\n");
  86                 return 0;
  87         }
  88
  89         int i;
  90         for (i = 0; i < argc; i++)
  91                 args[i] = argv[i];
  92
  93         args[argc] = NULL;
  94
  95         rc = task_spawnv(&id, argv[0], args);
  96
  97         free(args);
  98
  99         if (rc != EOK) {
 100                 fprintf(stderr, "%s: Error spawning %s (%s)\n", NAME, argv[0],
 101                     str_error(rc));
 102                 return 0;
 103         }
 104
 105         return id;
 106 }
 107
 108 int main(int argc, char *argv[])
 109 {
 110         if (argc < 3) {
 111                 usage();
 112                 return -1;
 113         }
 114
 115         int i;
 116         for (i = 1; i < argc; i++) {
 117                 if (str_cmp(argv[i], "-i") == 0) {
 118                         i++;
 119                         if (i >= argc) {
 120                                 usage();
 121                                 return -2;
 122                         }
 123                         reopen(&stdin, 0, argv[i], O_RDONLY, "r");
 124                 } else if (str_cmp(argv[i], "-o") == 0) {
 125                         i++;
 126                         if (i >= argc) {
 127                                 usage();
 128                                 return -3;
 129                         }
 130                         reopen(&stdout, 1, argv[i], O_WRONLY | O_CREAT, "w");
 131                 } else if (str_cmp(argv[i], "-e") == 0) {
 132                         i++;
 133                         if (i >= argc) {
 134                                 usage();
 135                                 return -4;
 136                         }
 137                         reopen(&stderr, 2, argv[i], O_WRONLY | O_CREAT, "w");
 138                 } else if (str_cmp(argv[i], "--") == 0) {
 139                         i++;
 140                         break;
 141                 }
 142         }
 143
 144         if (i >= argc) {
 145                 usage();
 146                 return -5;
 147         }
 148
 149         /*
 150          * FIXME: fdopen() should actually detect that we are opening a console
 151          * and it should set line-buffering mode automatically.
 152          */
 153         setvbuf(stdout, NULL, _IOLBF, BUFSIZ);
 154
 155         task_id_t id = spawn(argc - i, argv + i);
 156
 157         if (id != 0) {
 158                 task_exit_t texit;
 159                 int retval;
 160                 task_wait(id, &texit, &retval);
 161
 162                 return retval;
 163         }
 164
 165         return -6;
 166 }
 167
 168 /** @}
 169  */