| 1 | /* |
| 2 | * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU General Public License, version 2 only, as |
| 6 | * published by the Free Software Foundation. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 11 | * more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public License along with |
| 14 | * this program; if not, write to the Free Software Foundation, Inc., 51 |
| 15 | * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 16 | */ |
| 17 | |
| 18 | #define _GNU_SOURCE |
| 19 | #include <assert.h> |
| 20 | #include <ctype.h> |
| 21 | #include <fcntl.h> |
| 22 | #include <limits.h> |
| 23 | #include <stdlib.h> |
| 24 | #include <string.h> |
| 25 | #include <sys/types.h> |
| 26 | #include <sys/stat.h> |
| 27 | #include <unistd.h> |
| 28 | |
| 29 | #include <common/common.h> |
| 30 | |
| 31 | #include "utils.h" |
| 32 | |
| 33 | /* |
| 34 | * Return the realpath(3) of the path even if the last directory token does not |
| 35 | * exist. For example, with /tmp/test1/test2, if test2/ does not exist but the |
| 36 | * /tmp/test1 does, the real path is returned. In normal time, realpath(3) |
| 37 | * fails if the end point directory does not exist. |
| 38 | */ |
| 39 | __attribute__((visibility("hidden"))) |
| 40 | char *utils_expand_path(const char *path) |
| 41 | { |
| 42 | const char *end_path = path; |
| 43 | char *next, *cut_path = NULL, *expanded_path = NULL; |
| 44 | |
| 45 | /* Safety net */ |
| 46 | if (path == NULL) { |
| 47 | goto error; |
| 48 | } |
| 49 | |
| 50 | /* Find last token delimited by '/' */ |
| 51 | while ((next = strpbrk(end_path + 1, "/"))) { |
| 52 | end_path = next; |
| 53 | } |
| 54 | |
| 55 | /* Cut last token from original path */ |
| 56 | cut_path = strndup(path, end_path - path); |
| 57 | |
| 58 | expanded_path = zmalloc(PATH_MAX); |
| 59 | if (expanded_path == NULL) { |
| 60 | PERROR("zmalloc expand path"); |
| 61 | goto error; |
| 62 | } |
| 63 | |
| 64 | expanded_path = realpath((char *)cut_path, expanded_path); |
| 65 | if (expanded_path == NULL) { |
| 66 | switch (errno) { |
| 67 | case ENOENT: |
| 68 | ERR("%s: No such file or directory", cut_path); |
| 69 | break; |
| 70 | default: |
| 71 | PERROR("realpath utils expand path"); |
| 72 | break; |
| 73 | } |
| 74 | goto error; |
| 75 | } |
| 76 | |
| 77 | /* Add end part to expanded path */ |
| 78 | strncat(expanded_path, end_path, PATH_MAX - strlen(expanded_path) - 1); |
| 79 | |
| 80 | free(cut_path); |
| 81 | return expanded_path; |
| 82 | |
| 83 | error: |
| 84 | free(expanded_path); |
| 85 | free(cut_path); |
| 86 | return NULL; |
| 87 | } |
| 88 | |
| 89 | /* |
| 90 | * Create a pipe in dst. |
| 91 | */ |
| 92 | __attribute__((visibility("hidden"))) |
| 93 | int utils_create_pipe(int *dst) |
| 94 | { |
| 95 | int ret; |
| 96 | |
| 97 | if (dst == NULL) { |
| 98 | return -1; |
| 99 | } |
| 100 | |
| 101 | ret = pipe(dst); |
| 102 | if (ret < 0) { |
| 103 | PERROR("create pipe"); |
| 104 | } |
| 105 | |
| 106 | return ret; |
| 107 | } |
| 108 | |
| 109 | /* |
| 110 | * Create pipe and set CLOEXEC flag to both fd. |
| 111 | * |
| 112 | * Make sure the pipe opened by this function are closed at some point. Use |
| 113 | * utils_close_pipe(). |
| 114 | */ |
| 115 | __attribute__((visibility("hidden"))) |
| 116 | int utils_create_pipe_cloexec(int *dst) |
| 117 | { |
| 118 | int ret, i; |
| 119 | |
| 120 | if (dst == NULL) { |
| 121 | return -1; |
| 122 | } |
| 123 | |
| 124 | ret = utils_create_pipe(dst); |
| 125 | if (ret < 0) { |
| 126 | goto error; |
| 127 | } |
| 128 | |
| 129 | for (i = 0; i < 2; i++) { |
| 130 | ret = fcntl(dst[i], F_SETFD, FD_CLOEXEC); |
| 131 | if (ret < 0) { |
| 132 | PERROR("fcntl pipe cloexec"); |
| 133 | goto error; |
| 134 | } |
| 135 | } |
| 136 | |
| 137 | error: |
| 138 | return ret; |
| 139 | } |
| 140 | |
| 141 | /* |
| 142 | * Close both read and write side of the pipe. |
| 143 | */ |
| 144 | __attribute__((visibility("hidden"))) |
| 145 | void utils_close_pipe(int *src) |
| 146 | { |
| 147 | int i, ret; |
| 148 | |
| 149 | if (src == NULL) { |
| 150 | return; |
| 151 | } |
| 152 | |
| 153 | for (i = 0; i < 2; i++) { |
| 154 | /* Safety check */ |
| 155 | if (src[i] < 0) { |
| 156 | continue; |
| 157 | } |
| 158 | |
| 159 | ret = close(src[i]); |
| 160 | if (ret) { |
| 161 | PERROR("close pipe"); |
| 162 | } |
| 163 | } |
| 164 | } |
| 165 | |
| 166 | /* |
| 167 | * Create a new string using two strings range. |
| 168 | */ |
| 169 | __attribute__((visibility("hidden"))) |
| 170 | char *utils_strdupdelim(const char *begin, const char *end) |
| 171 | { |
| 172 | char *str; |
| 173 | |
| 174 | str = zmalloc(end - begin + 1); |
| 175 | if (str == NULL) { |
| 176 | PERROR("zmalloc strdupdelim"); |
| 177 | goto error; |
| 178 | } |
| 179 | |
| 180 | memcpy(str, begin, end - begin); |
| 181 | str[end - begin] = '\0'; |
| 182 | |
| 183 | error: |
| 184 | return str; |
| 185 | } |
| 186 | |
| 187 | /* |
| 188 | * Set CLOEXEC flag to the give file descriptor. |
| 189 | */ |
| 190 | __attribute__((visibility("hidden"))) |
| 191 | int utils_set_fd_cloexec(int fd) |
| 192 | { |
| 193 | int ret; |
| 194 | |
| 195 | if (fd < 0) { |
| 196 | ret = -EINVAL; |
| 197 | goto end; |
| 198 | } |
| 199 | |
| 200 | ret = fcntl(fd, F_SETFD, FD_CLOEXEC); |
| 201 | if (ret < 0) { |
| 202 | PERROR("fcntl cloexec"); |
| 203 | ret = -errno; |
| 204 | } |
| 205 | |
| 206 | end: |
| 207 | return ret; |
| 208 | } |
| 209 | |
| 210 | /* |
| 211 | * Create pid file to the given path and filename. |
| 212 | */ |
| 213 | __attribute__((visibility("hidden"))) |
| 214 | int utils_create_pid_file(pid_t pid, const char *filepath) |
| 215 | { |
| 216 | int ret; |
| 217 | FILE *fp; |
| 218 | |
| 219 | assert(filepath); |
| 220 | |
| 221 | fp = fopen(filepath, "w"); |
| 222 | if (fp == NULL) { |
| 223 | PERROR("open pid file %s", filepath); |
| 224 | ret = -1; |
| 225 | goto error; |
| 226 | } |
| 227 | |
| 228 | ret = fprintf(fp, "%d\n", pid); |
| 229 | if (ret < 0) { |
| 230 | PERROR("fprintf pid file"); |
| 231 | } |
| 232 | |
| 233 | fclose(fp); |
| 234 | DBG("Pid %d written in file %s", pid, filepath); |
| 235 | error: |
| 236 | return ret; |
| 237 | } |
| 238 | |
| 239 | /* |
| 240 | * Recursively create directory using the given path and mode. |
| 241 | * |
| 242 | * On success, return 0 else a negative error code. |
| 243 | */ |
| 244 | __attribute__((visibility("hidden"))) |
| 245 | int utils_mkdir_recursive(const char *path, mode_t mode) |
| 246 | { |
| 247 | char *p, tmp[PATH_MAX]; |
| 248 | struct stat statbuf; |
| 249 | size_t len; |
| 250 | int ret; |
| 251 | |
| 252 | assert(path); |
| 253 | |
| 254 | ret = snprintf(tmp, sizeof(tmp), "%s", path); |
| 255 | if (ret < 0) { |
| 256 | PERROR("snprintf mkdir"); |
| 257 | goto error; |
| 258 | } |
| 259 | |
| 260 | len = ret; |
| 261 | if (tmp[len - 1] == '/') { |
| 262 | tmp[len - 1] = 0; |
| 263 | } |
| 264 | |
| 265 | for (p = tmp + 1; *p; p++) { |
| 266 | if (*p == '/') { |
| 267 | *p = 0; |
| 268 | if (tmp[strlen(tmp) - 1] == '.' && |
| 269 | tmp[strlen(tmp) - 2] == '.' && |
| 270 | tmp[strlen(tmp) - 3] == '/') { |
| 271 | ERR("Using '/../' is not permitted in the trace path (%s)", |
| 272 | tmp); |
| 273 | ret = -1; |
| 274 | goto error; |
| 275 | } |
| 276 | ret = stat(tmp, &statbuf); |
| 277 | if (ret < 0) { |
| 278 | ret = mkdir(tmp, mode); |
| 279 | if (ret < 0) { |
| 280 | if (errno != EEXIST) { |
| 281 | PERROR("mkdir recursive"); |
| 282 | ret = -errno; |
| 283 | goto error; |
| 284 | } |
| 285 | } |
| 286 | } |
| 287 | *p = '/'; |
| 288 | } |
| 289 | } |
| 290 | |
| 291 | ret = mkdir(tmp, mode); |
| 292 | if (ret < 0) { |
| 293 | if (errno != EEXIST) { |
| 294 | PERROR("mkdir recursive last piece"); |
| 295 | ret = -errno; |
| 296 | } else { |
| 297 | ret = 0; |
| 298 | } |
| 299 | } |
| 300 | |
| 301 | error: |
| 302 | return ret; |
| 303 | } |