/*
* 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
* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#define _GNU_SOURCE
+#define _LGPL_SOURCE
#include <assert.h>
#include <ctype.h>
#include <fcntl.h>
#include <limits.h>
#include <stdlib.h>
-#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <inttypes.h>
-#include <regex.h>
#include <grp.h>
+#include <pwd.h>
+#include <sys/file.h>
+#include <unistd.h>
#include <common/common.h>
#include <common/runas.h>
+#include <common/compat/getenv.h>
+#include <common/compat/string.h>
+#include <common/compat/dirent.h>
+#include <lttng/constant.h>
#include "utils.h"
#include "defaults.h"
LTTNG_HIDDEN
char *utils_partial_realpath(const char *path, char *resolved_path, size_t size)
{
- char *cut_path, *try_path = NULL, *try_path_prev = NULL;
+ char *cut_path = NULL, *try_path = NULL, *try_path_prev = NULL;
const char *next, *prev, *end;
/* Safety net */
/* Resolve the canonical path of the first part of the path */
while (try_path != NULL && next != end) {
+ char *try_path_buf = NULL;
+
/*
* If there is not any '/' left, we want to try with
* the full path
}
/* Cut the part we will be trying to resolve */
- cut_path = strndup(path, next - path);
+ cut_path = lttng_strndup(path, next - path);
+ if (cut_path == NULL) {
+ PERROR("lttng_strndup");
+ goto error;
+ }
+
+ try_path_buf = zmalloc(LTTNG_PATH_MAX);
+ if (!try_path_buf) {
+ PERROR("zmalloc");
+ goto error;
+ }
/* Try to resolve this part */
- try_path = realpath((char *)cut_path, NULL);
+ try_path = realpath((char *) cut_path, try_path_buf);
if (try_path == NULL) {
+ free(try_path_buf);
/*
* There was an error, we just want to be assured it
* is linked to an unexistent directory, if it's another
}
} else {
/* Save the place we are before trying the next step */
+ try_path_buf = NULL;
free(try_path_prev);
try_path_prev = try_path;
prev = next;
/* Free the allocated memory */
free(cut_path);
- };
+ cut_path = NULL;
+ }
/* Allocate memory for the resolved path if necessary */
if (resolved_path == NULL) {
* path are pointers for the same memory space
*/
cut_path = strdup(prev);
+ if (cut_path == NULL) {
+ PERROR("strdup");
+ goto error;
+ }
/* Concatenate the strings */
snprintf(resolved_path, size, "%s%s", try_path_prev, cut_path);
/* Free the allocated memory */
free(cut_path);
free(try_path_prev);
+ cut_path = NULL;
+ try_path_prev = NULL;
/*
* Else, we just copy the path in our resolved_path to
* return it as is
error:
free(resolved_path);
- return NULL;
-}
-
-/*
- * 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
- */
-LTTNG_HIDDEN
-char *utils_resolve_relative(const char *path)
-{
- char *next, *previous, *slash, *start_path, *absolute_path = NULL;
-
- /* 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;
- }
-
- /* 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, "/./"))) {
-
- /* We prepare the start_path not containing it */
- start_path = strndup(absolute_path, next - absolute_path);
-
- /* And we concatenate it with the part after this string */
- snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 2);
-
- free(start_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);
- goto error;
- }
-
- /* We find the last level of directory */
- previous = absolute_path;
- while ((slash = strpbrk(previous + 1, "/")) && slash != next) {
- previous = slash;
- }
-
- /* 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 + 3);
-
- free(start_path);
- }
-
- return absolute_path;
-
-error:
- free(absolute_path);
+ free(cut_path);
return NULL;
}
char *utils_expand_path(const char *path)
{
char *next, *previous, *slash, *start_path, *absolute_path = NULL;
+ char *last_token;
+ int is_dot, is_dotdot;
/* Safety net */
if (path == NULL) {
if (*path != '/' && strncmp(path, "./", 2) != 0 &&
strncmp(path, "../", 3) != 0) {
snprintf(absolute_path, PATH_MAX, "./%s", path);
- /* Else, we just copy the path */
+ /* Else, we just copy the path */
} else {
strncpy(absolute_path, path, PATH_MAX);
}
while ((next = strstr(absolute_path, "/./"))) {
/* We prepare the start_path not containing it */
- start_path = strndup(absolute_path, next - absolute_path);
-
+ start_path = lttng_strndup(absolute_path, next - absolute_path);
+ if (!start_path) {
+ PERROR("lttng_strndup");
+ goto error;
+ }
/* And we concatenate it with the part after this string */
snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 2);
}
/* Then we prepare the start_path not containing it */
- start_path = strndup(absolute_path, previous - absolute_path);
+ start_path = lttng_strndup(absolute_path, previous - absolute_path);
+ if (!start_path) {
+ PERROR("lttng_strndup");
+ goto error;
+ }
/* And we concatenate it with the part after the '/../' */
snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 4);
absolute_path, PATH_MAX);
}
+ /* 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';
+ }
+ }
+
return absolute_path;
error:
goto error;
}
- ret = fprintf(fp, "%d\n", pid);
+ ret = fprintf(fp, "%d\n", (int) pid);
if (ret < 0) {
PERROR("fprintf pid file");
+ goto error;
+ }
+
+ if (fclose(fp)) {
+ PERROR("fclose");
+ }
+ DBG("Pid %d written in file %s", (int) pid, filepath);
+ ret = 0;
+error:
+ return ret;
+}
+
+/*
+ * Create lock file to the given path and filename.
+ * Returns the associated file descriptor, -1 on error.
+ */
+LTTNG_HIDDEN
+int utils_create_lock_file(const char *filepath)
+{
+ int ret;
+ int fd;
+ struct flock lock;
+
+ assert(filepath);
+
+ memset(&lock, 0, sizeof(lock));
+ fd = open(filepath, O_CREAT | O_WRONLY, S_IRUSR | S_IWUSR |
+ S_IRGRP | S_IWGRP);
+ if (fd < 0) {
+ PERROR("open lock file %s", filepath);
+ ret = -1;
+ goto error;
+ }
+
+ /*
+ * Attempt to lock the file. If this fails, there is
+ * already a process using the same lock file running
+ * and we should exit.
+ */
+ lock.l_whence = SEEK_SET;
+ lock.l_type = F_WRLCK;
+
+ ret = fcntl(fd, F_SETLK, &lock);
+ if (ret == -1) {
+ PERROR("fcntl lock file");
+ ERR("Could not get lock file %s, another instance is running.",
+ filepath);
+ if (close(fd)) {
+ PERROR("close lock file");
+ }
+ fd = ret;
+ goto error;
}
- fclose(fp);
- DBG("Pid %d written in file %s", pid, filepath);
error:
+ return fd;
+}
+
+/*
+ * On some filesystems (e.g. nfs), mkdir will validate access rights before
+ * checking for the existence of the path element. This means that on a setup
+ * where "/home/" is a mounted NFS share, and running as an unpriviledged user,
+ * recursively creating a path of the form "/home/my_user/trace/" will fail with
+ * EACCES on mkdir("/home", ...).
+ *
+ * Performing a stat(...) on the path to check for existence allows us to
+ * work around this behaviour.
+ */
+static
+int mkdir_check_exists(const char *path, mode_t mode)
+{
+ int ret = 0;
+ struct stat st;
+
+ ret = stat(path, &st);
+ if (ret == 0) {
+ if (S_ISDIR(st.st_mode)) {
+ /* Directory exists, skip. */
+ goto end;
+ } else {
+ /* Exists, but is not a directory. */
+ errno = ENOTDIR;
+ ret = -1;
+ goto end;
+ }
+ }
+
+ /*
+ * Let mkdir handle other errors as the caller expects mkdir
+ * semantics.
+ */
+ ret = mkdir(path, mode);
+end:
return ret;
}
/*
- * Recursively create directory using the given path and mode.
+ * Create directory using the given path and mode.
*
* On success, return 0 else a negative error code.
*/
LTTNG_HIDDEN
-int utils_mkdir_recursive(const char *path, mode_t mode)
+int utils_mkdir(const char *path, mode_t mode, int uid, int gid)
+{
+ int ret;
+
+ if (uid < 0 || gid < 0) {
+ ret = mkdir_check_exists(path, mode);
+ } else {
+ ret = run_as_mkdir(path, mode, uid, gid);
+ }
+ if (ret < 0) {
+ if (errno != EEXIST) {
+ PERROR("mkdir %s, uid %d, gid %d", path ? path : "NULL",
+ uid, gid);
+ } else {
+ ret = 0;
+ }
+ }
+
+ return ret;
+}
+
+/*
+ * Internal version of mkdir_recursive. Runs as the current user.
+ * Don't call directly; use utils_mkdir_recursive().
+ *
+ * This function is ominously marked as "unsafe" since it should only
+ * be called by a caller that has transitioned to the uid and gid under which
+ * the directory creation should occur.
+ */
+LTTNG_HIDDEN
+int _utils_mkdir_recursive_unsafe(const char *path, mode_t mode)
{
char *p, tmp[PATH_MAX];
size_t len;
ret = -1;
goto error;
}
- ret = mkdir(tmp, mode);
+ ret = mkdir_check_exists(tmp, mode);
if (ret < 0) {
- if (errno != EEXIST) {
+ if (errno != EACCES) {
PERROR("mkdir recursive");
ret = -errno;
goto error;
}
}
- ret = mkdir(tmp, mode);
+ ret = mkdir_check_exists(tmp, mode);
if (ret < 0) {
- if (errno != EEXIST) {
- PERROR("mkdir recursive last piece");
- ret = -errno;
- } else {
- ret = 0;
- }
+ PERROR("mkdir recursive last element");
+ ret = -errno;
}
error:
}
/*
- * Create the stream tracefile on disk.
+ * Recursively create directory using the given path and mode, under the
+ * provided uid and gid.
*
- * Return 0 on success or else a negative value.
+ * On success, return 0 else a negative error code.
*/
LTTNG_HIDDEN
-int utils_create_stream_file(const char *path_name, char *file_name, uint64_t size,
- uint64_t count, int uid, int gid, char *suffix)
+int utils_mkdir_recursive(const char *path, mode_t mode, int uid, int gid)
{
- int ret, out_fd, flags, mode;
- char full_path[PATH_MAX], *path_name_suffix = NULL, *path;
- char *extra = NULL;
+ int ret;
- assert(path_name);
- assert(file_name);
+ if (uid < 0 || gid < 0) {
+ /* Run as current user. */
+ ret = _utils_mkdir_recursive_unsafe(path, mode);
+ } else {
+ ret = run_as_mkdir_recursive(path, mode, uid, gid);
+ }
+ if (ret < 0) {
+ PERROR("mkdir %s, uid %d, gid %d", path ? path : "NULL",
+ uid, gid);
+ }
+
+ return ret;
+}
+
+/*
+ * path is the output parameter. It needs to be PATH_MAX len.
+ *
+ * Return 0 on success or else a negative value.
+ */
+static int utils_stream_file_name(char *path,
+ const char *path_name, const char *file_name,
+ uint64_t size, uint64_t count,
+ const char *suffix)
+{
+ int ret;
+ char full_path[PATH_MAX];
+ char *path_name_suffix = NULL;
+ char *extra = NULL;
ret = snprintf(full_path, sizeof(full_path), "%s/%s",
path_name, file_name);
}
/*
- * If we split the trace in multiple files, we have to add the count at the
- * end of the tracefile name
+ * If we split the trace in multiple files, we have to add the count at
+ * the end of the tracefile name.
*/
if (extra) {
ret = asprintf(&path_name_suffix, "%s%s", full_path, extra);
PERROR("Allocating path name with extra string");
goto error_free_suffix;
}
- path = path_name_suffix;
+ strncpy(path, path_name_suffix, PATH_MAX - 1);
+ path[PATH_MAX - 1] = '\0';
} else {
- path = full_path;
+ strncpy(path, full_path, PATH_MAX - 1);
+ }
+ path[PATH_MAX - 1] = '\0';
+ ret = 0;
+
+ free(path_name_suffix);
+error_free_suffix:
+ free(extra);
+error:
+ return ret;
+}
+
+/*
+ * Create the stream file on disk.
+ *
+ * Return 0 on success or else a negative value.
+ */
+LTTNG_HIDDEN
+int utils_create_stream_file(const char *path_name, char *file_name, uint64_t size,
+ uint64_t count, int uid, int gid, char *suffix)
+{
+ int ret, flags, mode;
+ char path[PATH_MAX];
+
+ ret = utils_stream_file_name(path, path_name, file_name,
+ size, count, suffix);
+ if (ret < 0) {
+ goto error;
}
flags = O_WRONLY | O_CREAT | O_TRUNC;
mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP;
if (uid < 0 || gid < 0) {
- out_fd = open(path, flags, mode);
+ ret = open(path, flags, mode);
} else {
- out_fd = run_as_open(path, flags, mode, uid, gid);
+ ret = run_as_open(path, flags, mode, uid, gid);
}
- if (out_fd < 0) {
+ if (ret < 0) {
PERROR("open stream path %s", path);
- goto error_open;
}
- ret = out_fd;
+error:
+ return ret;
+}
-error_open:
- free(path_name_suffix);
-error_free_suffix:
- free(extra);
+/*
+ * Unlink the stream tracefile from disk.
+ *
+ * Return 0 on success or else a negative value.
+ */
+LTTNG_HIDDEN
+int utils_unlink_stream_file(const char *path_name, char *file_name, uint64_t size,
+ uint64_t count, int uid, int gid, char *suffix)
+{
+ int ret;
+ char path[PATH_MAX];
+
+ ret = utils_stream_file_name(path, path_name, file_name,
+ size, count, suffix);
+ if (ret < 0) {
+ goto error;
+ }
+ if (uid < 0 || gid < 0) {
+ ret = unlink(path);
+ } else {
+ ret = run_as_unlink(path, uid, gid);
+ }
+ if (ret < 0) {
+ goto error;
+ }
error:
+ DBG("utils_unlink_stream_file %s returns %d", path, ret);
return ret;
}
}
if (count > 0) {
+ /*
+ * In tracefile rotation, for the relay daemon we need
+ * to unlink the old file if present, because it may
+ * still be open in reading by the live thread, and we
+ * need to ensure that we do not overwrite the content
+ * between get_index and get_packet. Since we have no
+ * way to verify integrity of the data content compared
+ * to the associated index, we need to ensure the reader
+ * has exclusive access to the file content, and that
+ * the open of the data file is performed in get_index.
+ * Unlinking the old file rather than overwriting it
+ * achieves this.
+ */
*new_count = (*new_count + 1) % count;
+ ret = utils_unlink_stream_file(path_name, file_name,
+ size, *new_count, uid, gid, 0);
+ if (ret < 0 && errno != ENOENT) {
+ goto error;
+ }
} else {
(*new_count)++;
}
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;
}
char *utils_get_home_dir(void)
{
char *val = NULL;
- val = getenv(DEFAULT_LTTNG_HOME_ENV_VAR);
+ struct passwd *pwd;
+
+ val = lttng_secure_getenv(DEFAULT_LTTNG_HOME_ENV_VAR);
+ if (val != NULL) {
+ goto end;
+ }
+ val = lttng_secure_getenv(DEFAULT_LTTNG_FALLBACK_HOME_ENV_VAR);
if (val != NULL) {
- return val;
+ goto end;
}
- return getenv(DEFAULT_LTTNG_FALLBACK_HOME_ENV_VAR);
+
+ /* Fallback on the password file entry. */
+ pwd = getpwuid(getuid());
+ if (!pwd) {
+ goto end;
+ }
+ val = pwd->pw_dir;
+
+ DBG3("Home directory is '%s'", val);
+
+end:
+ return val;
+}
+
+/**
+ * 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;
+}
+
+/*
+ * Obtain the value of LTTNG_KMOD_PROBES environment variable, if exists.
+ * Otherwise returns NULL.
+ */
+LTTNG_HIDDEN
+char *utils_get_kmod_probes_list(void)
+{
+ return lttng_secure_getenv(DEFAULT_LTTNG_KMOD_PROBES);
+}
+
+/*
+ * Obtain the value of LTTNG_EXTRA_KMOD_PROBES environment variable, if
+ * exists. Otherwise returns NULL.
+ */
+LTTNG_HIDDEN
+char *utils_get_extra_kmod_probes_list(void)
+{
+ return lttng_secure_getenv(DEFAULT_LTTNG_EXTRA_KMOD_PROBES);
}
/*
timeinfo = localtime(&rawtime);
ret = strftime(dst, len, format, timeinfo);
if (ret == 0) {
- ERR("Unable to strftime with format %s at dst %p of len %lu", format,
+ ERR("Unable to strftime with format %s at dst %p of len %zu", format,
dst, len);
}
}
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;
+ }
+
+ if (long_options[i].val != '\0') {
+ optstring[str_pos++] = (char) long_options[i].val;
+ if (long_options[i].has_arg) {
+ optstring[str_pos++] = ':';
+ }
+ }
+ }
+
+end:
+ return optstring;
+}
+
+/*
+ * Try to remove a hierarchy of empty directories, recursively. Don't unlink
+ * any file. Try to rmdir any empty directory within the hierarchy.
+ */
+LTTNG_HIDDEN
+int utils_recursive_rmdir(const char *path)
+{
+ DIR *dir;
+ size_t path_len;
+ int dir_fd, ret = 0, closeret, is_empty = 1;
+ struct dirent *entry;
+
+ /* Open directory */
+ dir = opendir(path);
+ if (!dir) {
+ PERROR("Cannot open '%s' path", path);
+ return -1;
+ }
+ dir_fd = lttng_dirfd(dir);
+ if (dir_fd < 0) {
+ PERROR("lttng_dirfd");
+ return -1;
+ }
+
+ path_len = strlen(path);
+ while ((entry = readdir(dir))) {
+ struct stat st;
+ size_t name_len;
+ char filename[PATH_MAX];
+
+ if (!strcmp(entry->d_name, ".")
+ || !strcmp(entry->d_name, "..")) {
+ continue;
+ }
+
+ name_len = strlen(entry->d_name);
+ if (path_len + name_len + 2 > sizeof(filename)) {
+ ERR("Failed to remove file: path name too long (%s/%s)",
+ path, entry->d_name);
+ continue;
+ }
+ if (snprintf(filename, sizeof(filename), "%s/%s",
+ path, entry->d_name) < 0) {
+ ERR("Failed to format path.");
+ continue;
+ }
+
+ if (stat(filename, &st)) {
+ PERROR("stat");
+ continue;
+ }
+
+ if (S_ISDIR(st.st_mode)) {
+ char subpath[PATH_MAX];
+
+ strncpy(subpath, path, PATH_MAX);
+ subpath[PATH_MAX - 1] = '\0';
+ strncat(subpath, "/",
+ PATH_MAX - strlen(subpath) - 1);
+ strncat(subpath, entry->d_name,
+ PATH_MAX - strlen(subpath) - 1);
+ if (utils_recursive_rmdir(subpath)) {
+ is_empty = 0;
+ }
+ } else if (S_ISREG(st.st_mode)) {
+ is_empty = 0;
+ } else {
+ ret = -EINVAL;
+ goto end;
+ }
+ }
+end:
+ closeret = closedir(dir);
+ if (closeret) {
+ PERROR("closedir");
+ }
+ if (is_empty) {
+ DBG3("Attempting rmdir %s", path);
+ ret = rmdir(path);
+ }
+ return ret;
+}
projects / lttng-tools.git / blobdiff