/*
* Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
+ * Copyright (C) 2013 - Raphaël Beamonte <raphael.beamonte@gmail.com>
+ * Copyright (C) 2013 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License, version 2 only, as
#include <sys/types.h>
#include <unistd.h>
#include <inttypes.h>
-#include <regex.h>
#include <grp.h>
+#include <pwd.h>
#include <common/common.h>
#include <common/runas.h>
#include "defaults.h"
/*
- * Resolve the './' and '../' strings in the middle of a path using
- * our very own way to do it, so that it works even if the directory
- * does not exist
+ * Return a partial realpath(3) of the path even if the full path does not
+ * exist. For instance, with /tmp/test1/test2/test3, if test2/ does not exist
+ * but the /tmp/test1 does, the real path for /tmp/test1 is concatened with
+ * /test2/test3 then returned. In normal time, realpath(3) fails if the end
+ * point directory does not exist.
+ * In case resolved_path is NULL, the string returned was allocated in the
+ * function and thus need to be freed by the caller. The size argument allows
+ * to specify the size of the resolved_path argument if given, or the size to
+ * allocate.
*/
LTTNG_HIDDEN
-char *utils_resolve_relative(const char *path)
+char *utils_partial_realpath(const char *path, char *resolved_path, size_t size)
{
- char *next, *previous, *slash, *start_path, *absolute_path = NULL;
+ char *cut_path, *try_path = NULL, *try_path_prev = NULL;
+ const char *next, *prev, *end;
/* Safety net */
if (path == NULL) {
goto error;
}
- /* Allocate memory for the absolute path */
- absolute_path = zmalloc(PATH_MAX);
- if (absolute_path == NULL) {
- PERROR("zmalloc expand path");
- goto error;
+ /*
+ * Identify the end of the path, we don't want to treat the
+ * last char if it is a '/', we will just keep it on the side
+ * to be added at the end, and return a value coherent with
+ * the path given as argument
+ */
+ end = path + strlen(path);
+ if (*(end-1) == '/') {
+ end--;
}
- /* Copy the path in the absolute path */
- strncpy(absolute_path, path, PATH_MAX);
-
- /* As long as we find '/./' in the path string */
- while ((next = strstr(absolute_path, "/./"))) {
+ /* Initiate the values of the pointers before looping */
+ next = path;
+ prev = next;
+ /* Only to ensure try_path is not NULL to enter the while */
+ try_path = (char *)next;
- /* We prepare the start_path not containing it */
- start_path = strndup(absolute_path, next - absolute_path);
+ /* Resolve the canonical path of the first part of the path */
+ while (try_path != NULL && next != end) {
+ /*
+ * If there is not any '/' left, we want to try with
+ * the full path
+ */
+ next = strpbrk(next + 1, "/");
+ if (next == NULL) {
+ next = end;
+ }
- /* And we concatenate it with the part after this string */
- snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 2);
+ /* Cut the part we will be trying to resolve */
+ cut_path = strndup(path, next - path);
+
+ /* Try to resolve this part */
+ try_path = realpath((char *)cut_path, NULL);
+ if (try_path == NULL) {
+ /*
+ * There was an error, we just want to be assured it
+ * is linked to an unexistent directory, if it's another
+ * reason, we spawn an error
+ */
+ switch (errno) {
+ case ENOENT:
+ /* Ignore the error */
+ break;
+ default:
+ PERROR("realpath (partial_realpath)");
+ goto error;
+ break;
+ }
+ } else {
+ /* Save the place we are before trying the next step */
+ free(try_path_prev);
+ try_path_prev = try_path;
+ prev = next;
+ }
- free(start_path);
- }
+ /* Free the allocated memory */
+ free(cut_path);
+ };
- /* As long as we find '/../' in the path string */
- while ((next = strstr(absolute_path, "/../"))) {
- /* If the path starts with '/../', there's a problem */
- if (next == absolute_path) {
- ERR("%s: Path cannot be resolved", path);
+ /* Allocate memory for the resolved path if necessary */
+ if (resolved_path == NULL) {
+ resolved_path = zmalloc(size);
+ if (resolved_path == NULL) {
+ PERROR("zmalloc resolved path");
goto error;
}
+ }
- /* We find the last level of directory */
- previous = absolute_path;
- while ((slash = strpbrk(previous + 1, "/")) && slash != next) {
- previous = slash;
+ /*
+ * If we were able to solve at least partially the path, we can concatenate
+ * what worked and what didn't work
+ */
+ if (try_path_prev != NULL) {
+ /* If we risk to concatenate two '/', we remove one of them */
+ if (try_path_prev[strlen(try_path_prev) - 1] == '/' && prev[0] == '/') {
+ try_path_prev[strlen(try_path_prev) - 1] = '\0';
}
- /* Then we prepare the start_path not containing it */
- start_path = strndup(absolute_path, previous - absolute_path);
+ /*
+ * Duplicate the memory used by prev in case resolved_path and
+ * path are pointers for the same memory space
+ */
+ cut_path = strdup(prev);
- /* And we concatenate it with the part after the '/../' */
- snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 3);
+ /* Concatenate the strings */
+ snprintf(resolved_path, size, "%s%s", try_path_prev, cut_path);
- free(start_path);
+ /* Free the allocated memory */
+ free(cut_path);
+ free(try_path_prev);
+ /*
+ * Else, we just copy the path in our resolved_path to
+ * return it as is
+ */
+ } else {
+ strncpy(resolved_path, path, size);
}
- return absolute_path;
+ /* Then we return the 'partially' resolved path */
+ return resolved_path;
error:
- free(absolute_path);
+ free(resolved_path);
return NULL;
}
-
/*
- * Return the realpath(3) of the path even if the last directory token does not
- * exist. For example, with /tmp/test1/test2, if test2/ does not exist but the
- * /tmp/test1 does, the real path is returned. In normal time, realpath(3)
- * fails if the end point directory does not exist.
+ * Make a full resolution of the given path even if it doesn't exist.
+ * This function uses the utils_partial_realpath function to resolve
+ * symlinks and relatives paths at the start of the string, and
+ * implements functionnalities to resolve the './' and '../' strings
+ * in the middle of a path. This function is only necessary because
+ * realpath(3) does not accept to resolve unexistent paths.
+ * The returned string was allocated in the function, it is thus of
+ * the responsibility of the caller to free this memory.
*/
LTTNG_HIDDEN
char *utils_expand_path(const char *path)
{
- const char *end_path = NULL;
- char *next, *cut_path = NULL, *expanded_path = NULL;
+ char *next, *previous, *slash, *start_path, *absolute_path = NULL;
+ char *last_token;
+ int is_dot, is_dotdot;
/* Safety net */
if (path == NULL) {
goto error;
}
- /* Allocate memory for the expanded path */
- expanded_path = zmalloc(PATH_MAX);
- if (expanded_path == NULL) {
+ /* Allocate memory for the absolute_path */
+ absolute_path = zmalloc(PATH_MAX);
+ if (absolute_path == NULL) {
PERROR("zmalloc expand path");
goto error;
}
- /* If given path is already absolute */
- if (*path == '/') {
- strncpy(expanded_path, path, PATH_MAX);
- /* Else, we have some work to do */
+ /*
+ * If the path is not already absolute nor explicitly relative,
+ * consider we're in the current directory
+ */
+ if (*path != '/' && strncmp(path, "./", 2) != 0 &&
+ strncmp(path, "../", 3) != 0) {
+ snprintf(absolute_path, PATH_MAX, "./%s", path);
+ /* Else, we just copy the path */
} else {
- /* Pointer to the last char of the path */
- const char *last_char = path + strlen(path) - 1;
+ strncpy(absolute_path, path, PATH_MAX);
+ }
- end_path = path;
+ /* Resolve partially our path */
+ absolute_path = utils_partial_realpath(absolute_path,
+ absolute_path, PATH_MAX);
- /* Split part that will be resolved by realpath (relative path from
- * current directory using ./ or ../ only) and part that could not
- * (directory names)
- */
- while ((next = strpbrk(end_path, "/")) && (next != last_char)) {
- end_path = next + 1;
- if (strncmp(end_path, "./", 2) != 0 &&
- strncmp(end_path, "../", 3) != 0) {
- break;
- }
- }
+ /* As long as we find '/./' in the working_path string */
+ while ((next = strstr(absolute_path, "/./"))) {
- /* If this is the end of the string, and we still can resolve it */
- if (strncmp(end_path, "..\0", 3) == 0 ||
- strncmp(end_path, ".\0", 2) == 0) {
- end_path += strlen(end_path);
- }
+ /* We prepare the start_path not containing it */
+ start_path = strndup(absolute_path, next - absolute_path);
- /* If the end part is the whole path, we are in the current dir */
- if (end_path == path) {
- cut_path = strdup(".");
- /* Else, cut the resolvable part from original path */
- } else {
- cut_path = strndup(path, end_path - path);
- }
+ /* And we concatenate it with the part after this string */
+ snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 2);
- /* Resolve the canonical path of the first part of the path */
- expanded_path = realpath((char *)cut_path, expanded_path);
- if (expanded_path == NULL) {
- switch (errno) {
- case ENOENT:
- ERR("%s: No such file or directory", cut_path);
- break;
- default:
- PERROR("realpath utils expand path");
- break;
- }
- goto error;
- }
+ free(start_path);
+ }
- /* Add end part to expanded path if not empty */
- if (*end_path != 0) {
- strncat(expanded_path, "/", PATH_MAX - strlen(expanded_path) - 1);
- strncat(expanded_path, end_path,
- PATH_MAX - strlen(expanded_path) - 1);
+ /* As long as we find '/../' in the working_path string */
+ while ((next = strstr(absolute_path, "/../"))) {
+ /* We find the last level of directory */
+ previous = absolute_path;
+ while ((slash = strpbrk(previous, "/")) && slash != next) {
+ previous = slash + 1;
}
+
+ /* Then we prepare the start_path not containing it */
+ start_path = strndup(absolute_path, previous - absolute_path);
+
+ /* And we concatenate it with the part after the '/../' */
+ snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 4);
+
+ /* We can free the memory used for the start path*/
+ free(start_path);
+
+ /* Then we verify for symlinks using partial_realpath */
+ absolute_path = utils_partial_realpath(absolute_path,
+ absolute_path, PATH_MAX);
}
- /* Resolve the internal './' and '../' strings */
- next = utils_resolve_relative(expanded_path);
- if (next == NULL) {
- goto error;
+ /* Identify the last token */
+ last_token = strrchr(absolute_path, '/');
+
+ /* Verify that this token is not a relative path */
+ is_dotdot = (strcmp(last_token, "/..") == 0);
+ is_dot = (strcmp(last_token, "/.") == 0);
+
+ /* If it is, take action */
+ if (is_dot || is_dotdot) {
+ /* For both, remove this token */
+ *last_token = '\0';
+
+ /* If it was a reference to parent directory, go back one more time */
+ if (is_dotdot) {
+ last_token = strrchr(absolute_path, '/');
+
+ /* If there was only one level left, we keep the first '/' */
+ if (last_token == absolute_path) {
+ last_token++;
+ }
+
+ *last_token = '\0';
+ }
}
- free(expanded_path);
- free(cut_path);
- return next;
+ return absolute_path;
error:
- free(expanded_path);
- free(cut_path);
+ free(absolute_path);
return NULL;
}
return ret;
}
-/**
- * Prints the error message corresponding to a regex error code.
- *
- * @param errcode The error code.
- * @param regex The regex object that produced the error code.
- */
-static void regex_print_error(int errcode, regex_t *regex)
-{
- /* Get length of error message and allocate accordingly */
- size_t length;
- char *buffer;
-
- assert(regex != NULL);
-
- length = regerror(errcode, regex, NULL, 0);
- if (length == 0) {
- ERR("regerror returned a length of 0");
- return;
- }
-
- buffer = zmalloc(length);
- if (!buffer) {
- ERR("regex_print_error: zmalloc failed");
- return;
- }
-
- /* Get and print error message */
- regerror(errcode, regex, buffer, length);
- ERR("regex error: %s\n", buffer);
- free(buffer);
-
-}
/**
* Parse a string that represents a size in human readable format. It
- * supports decimal integers suffixed by 'k', 'M' or 'G'.
+ * supports decimal integers suffixed by 'k', 'K', 'M' or 'G'.
*
* The suffix multiply the integer by:
* 'k': 1024
* 'G': 1024^3
*
* @param str The string to parse.
- * @param size Pointer to a size_t that will be filled with the
+ * @param size Pointer to a uint64_t that will be filled with the
* resulting size.
*
* @return 0 on success, -1 on failure.
*/
LTTNG_HIDDEN
-int utils_parse_size_suffix(char *str, uint64_t *size)
+int utils_parse_size_suffix(const char * const str, uint64_t * const size)
{
- regex_t regex;
int ret;
- const int nmatch = 3;
- regmatch_t suffix_match, matches[nmatch];
- unsigned long long base_size;
+ uint64_t base_size;
long shift = 0;
+ const char *str_end;
+ char *num_end;
if (!str) {
- return 0;
- }
-
- /* Compile regex */
- ret = regcomp(®ex, "^\\(0x\\)\\{0,1\\}[0-9][0-9]*\\([kKMG]\\{0,1\\}\\)$", 0);
- if (ret != 0) {
- regex_print_error(ret, ®ex);
+ DBG("utils_parse_size_suffix: received a NULL string.");
ret = -1;
goto end;
}
- /* Match regex */
- ret = regexec(®ex, str, nmatch, matches, 0);
- if (ret != 0) {
+ /* strtoull will accept a negative number, but we don't want to. */
+ if (strchr(str, '-') != NULL) {
+ DBG("utils_parse_size_suffix: invalid size string, should not contain '-'.");
ret = -1;
- goto free;
+ goto end;
}
- /* There is a match ! */
+ /* str_end will point to the \0 */
+ str_end = str + strlen(str);
errno = 0;
- base_size = strtoull(str, NULL, 0);
+ base_size = strtoull(str, &num_end, 0);
if (errno != 0) {
- PERROR("strtoull");
+ PERROR("utils_parse_size_suffix strtoull");
ret = -1;
- goto free;
+ goto end;
}
- /* Check if there is a suffix */
- suffix_match = matches[2];
- if (suffix_match.rm_eo - suffix_match.rm_so == 1) {
- switch (*(str + suffix_match.rm_so)) {
- case 'K':
- case 'k':
- shift = KIBI_LOG2;
- break;
- case 'M':
- shift = MEBI_LOG2;
- break;
- case 'G':
- shift = GIBI_LOG2;
- break;
- default:
- ERR("parse_human_size: invalid suffix");
- ret = -1;
- goto free;
- }
+ if (num_end == str) {
+ /* strtoull parsed nothing, not good. */
+ DBG("utils_parse_size_suffix: strtoull had nothing good to parse.");
+ ret = -1;
+ goto end;
+ }
+
+ /* Check if a prefix is present. */
+ switch (*num_end) {
+ case 'G':
+ shift = GIBI_LOG2;
+ num_end++;
+ break;
+ case 'M': /* */
+ shift = MEBI_LOG2;
+ num_end++;
+ break;
+ case 'K':
+ case 'k':
+ shift = KIBI_LOG2;
+ num_end++;
+ break;
+ case '\0':
+ break;
+ default:
+ DBG("utils_parse_size_suffix: invalid suffix.");
+ ret = -1;
+ goto end;
+ }
+
+ /* Check for garbage after the valid input. */
+ if (num_end != str_end) {
+ DBG("utils_parse_size_suffix: Garbage after size string.");
+ ret = -1;
+ goto end;
}
*size = base_size << shift;
/* Check for overflow */
if ((*size >> shift) != base_size) {
- ERR("parse_size_suffix: oops, overflow detected.");
+ DBG("utils_parse_size_suffix: oops, overflow detected.");
ret = -1;
- goto free;
+ goto end;
}
ret = 0;
-
-free:
- regfree(®ex);
end:
return ret;
}
return getenv(DEFAULT_LTTNG_FALLBACK_HOME_ENV_VAR);
}
+/**
+ * Get user's home directory. Dynamically allocated, must be freed
+ * by the caller.
+ */
+LTTNG_HIDDEN
+char *utils_get_user_home_dir(uid_t uid)
+{
+ struct passwd pwd;
+ struct passwd *result;
+ char *home_dir = NULL;
+ char *buf = NULL;
+ long buflen;
+ int ret;
+
+ buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
+ if (buflen == -1) {
+ goto end;
+ }
+retry:
+ buf = zmalloc(buflen);
+ if (!buf) {
+ goto end;
+ }
+
+ ret = getpwuid_r(uid, &pwd, buf, buflen, &result);
+ if (ret || !result) {
+ if (ret == ERANGE) {
+ free(buf);
+ buflen *= 2;
+ goto retry;
+ }
+ goto end;
+ }
+
+ home_dir = strdup(pwd.pw_dir);
+end:
+ free(buf);
+ return home_dir;
+}
+
/*
* With the given format, fill dst with the time of len maximum siz.
*
}
return grp->gr_gid;
}
+
+/*
+ * Return a newly allocated option string. This string is to be used as the
+ * optstring argument of getopt_long(), see GETOPT(3). opt_count is the number
+ * of elements in the long_options array. Returns NULL if the string's
+ * allocation fails.
+ */
+LTTNG_HIDDEN
+char *utils_generate_optstring(const struct option *long_options,
+ size_t opt_count)
+{
+ int i;
+ size_t string_len = opt_count, str_pos = 0;
+ char *optstring;
+
+ /*
+ * Compute the necessary string length. One letter per option, two when an
+ * argument is necessary, and a trailing NULL.
+ */
+ for (i = 0; i < opt_count; i++) {
+ string_len += long_options[i].has_arg ? 1 : 0;
+ }
+
+ optstring = zmalloc(string_len);
+ if (!optstring) {
+ goto end;
+ }
+
+ for (i = 0; i < opt_count; i++) {
+ if (!long_options[i].name) {
+ /* Got to the trailing NULL element */
+ break;
+ }
+
+ optstring[str_pos++] = (char)long_options[i].val;
+ if (long_options[i].has_arg) {
+ optstring[str_pos++] = ':';
+ }
+ }
+
+end:
+ return optstring;
+}
projects / lttng-tools.git / blobdiff