src/bin/lttng/utils.c

   1 /*
   2  * Copyright (c)  2011 David Goulet <david.goulet@polymtl.ca>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License, version 2 only,
   6  * as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _GNU_SOURCE
  19 #include <stdlib.h>
  20 #include <ctype.h>
  21 #include <limits.h>
  22
  23 #include <common/error.h>
  24
  25 #include "conf.h"
  26 #include "utils.h"
  27
  28 /*
  29  * Return the realpath(3) of the path even if the last directory token does not
  30  * exist. For example, with /tmp/test1/test2, if test2/ does not exist but the
  31  * /tmp/test1 does, the real path is returned. In normal time, realpath(3)
  32  * fails if the end point directory does not exist.
  33  */
  34 char *expand_full_path(const char *path)
  35 {
  36         const char *end_path = path;
  37         char *next, *cut_path, *expanded_path;
  38
  39         /* Find last token delimited by '/' */
  40         while ((next = strpbrk(end_path + 1, "/"))) {
  41                 end_path = next;
  42         }
  43
  44         /* Cut last token from original path */
  45         cut_path = strndup(path, end_path - path);
  46
  47         expanded_path = malloc(PATH_MAX);
  48         if (expanded_path == NULL) {
  49                 goto error;
  50         }
  51
  52         expanded_path = realpath((char *)cut_path, expanded_path);
  53         if (expanded_path == NULL) {
  54                 switch (errno) {
  55                 case ENOENT:
  56                         ERR("%s: No such file or directory", cut_path);
  57                         break;
  58                 default:
  59                         perror("realpath");
  60                         break;
  61                 }
  62                 goto error;
  63         }
  64
  65         /* Add end part to expanded path */
  66         strcat(expanded_path, end_path);
  67
  68         free(cut_path);
  69         return expanded_path;
  70
  71 error:
  72         free(cut_path);
  73         return NULL;
  74 }
  75
  76 /*
  77  *  get_session_name
  78  *
  79  *  Return allocated string with the session name found in the config
  80  *  directory.
  81  */
  82 char *get_session_name(void)
  83 {
  84         char *path, *session_name = NULL;
  85
  86         /* Get path to config file */
  87         path = config_get_default_path();
  88         if (path == NULL) {
  89                 goto error;
  90         }
  91
  92         /* Get session name from config */
  93         session_name = config_read_session_name(path);
  94         if (session_name == NULL) {
  95                 goto error;
  96         }
  97
  98         DBG2("Config file path found: %s", path);
  99         DBG("Session name found: %s", session_name);
 100         return session_name;
 101
 102 error:
 103         return NULL;
 104 }
 105
 106
 107 /*
 108  * list_cmd_options
 109  *
 110  * Prints a simple list of the options available to a command. This is intended
 111  * to be easily parsed for bash completion.
 112  */
 113 void list_cmd_options(FILE *ofp, struct poptOption *options)
 114 {
 115         int i;
 116         struct poptOption *option = NULL;
 117
 118         for (i = 0; options[i].longName != NULL; i++) {
 119                 option = &options[i];
 120
 121                 fprintf(ofp, "--%s\n", option->longName);
 122
 123                 if (isprint(option->shortName)) {
 124                         fprintf(ofp, "-%c\n", option->shortName);
 125                 }
 126         }
 127 }