* 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 <grp.h>
#include <pwd.h>
#include <sys/file.h>
-#include <dirent.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("strndup");
+ 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) {
/* 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);
+ free(cut_path);
+ free(try_path);
+ if (try_path_prev != try_path) {
+ free(try_path_prev);
+ }
return NULL;
}
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("strndup");
+ PERROR("lttng_strndup");
goto error;
}
/* And we concatenate it with the part after this string */
}
/* 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("strndup");
+ PERROR("lttng_strndup");
goto 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", pid, filepath);
+ DBG("Pid %d written in file %s", (int) pid, filepath);
ret = 0;
error:
return ret;
{
int ret;
int fd;
+ struct flock lock;
assert(filepath);
- fd = open(filepath, O_CREAT,
- O_WRONLY | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
+ 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;
* already a process using the same lock file running
* and we should exit.
*/
- ret = flock(fd, LOCK_EX | LOCK_NB);
- if (ret) {
+ 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)) {
}
/*
- * Recursively create directory using the given path and mode.
+ * 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;
+}
+
+/*
+ * 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;
}
{
int ret;
- assert(new_count);
assert(stream_fd);
ret = close(out_fd);
PERROR("Closing tracefile");
goto error;
}
+ *stream_fd = -1;
if (count > 0) {
- *new_count = (*new_count + 1) % count;
+ /*
+ * 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.
+ */
+ if (new_count) {
+ *new_count = (*new_count + 1) % count;
+ }
+ ret = utils_unlink_stream_file(path_name, file_name, size,
+ new_count ? *new_count : 0, uid, gid, 0);
+ if (ret < 0 && errno != ENOENT) {
+ goto error;
+ }
} else {
- (*new_count)++;
+ if (new_count) {
+ (*new_count)++;
+ }
}
- ret = utils_create_stream_file(path_name, file_name, size, *new_count,
- uid, gid, 0);
+ ret = utils_create_stream_file(path_name, file_name, size,
+ new_count ? *new_count : 0, uid, gid, 0);
if (ret < 0) {
goto error;
}
break;
}
- optstring[str_pos++] = (char)long_options[i].val;
- if (long_options[i].has_arg) {
- optstring[str_pos++] = ':';
+ if (long_options[i].val != '\0') {
+ optstring[str_pos++] = (char) long_options[i].val;
+ if (long_options[i].has_arg) {
+ optstring[str_pos++] = ':';
+ }
}
}
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;
PERROR("Cannot open '%s' path", path);
return -1;
}
- dir_fd = dirfd(dir);
+ dir_fd = lttng_dirfd(dir);
if (dir_fd < 0) {
- PERROR("dirfd");
+ 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, ".."))
+ || !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;
- switch (entry->d_type) {
- case DT_DIR:
- {
+ }
+
+ if (stat(filename, &st)) {
+ PERROR("stat");
+ continue;
+ }
+
+ if (S_ISDIR(st.st_mode)) {
char subpath[PATH_MAX];
strncpy(subpath, path, PATH_MAX);
if (utils_recursive_rmdir(subpath)) {
is_empty = 0;
}
- break;
- }
- case DT_REG:
+ } else if (S_ISREG(st.st_mode)) {
is_empty = 0;
- break;
- default:
+ } else {
ret = -EINVAL;
goto end;
}
}
return ret;
}
+
+LTTNG_HIDDEN
+int utils_truncate_stream_file(int fd, off_t length)
+{
+ int ret;
+
+ ret = ftruncate(fd, length);
+ if (ret < 0) {
+ PERROR("ftruncate");
+ goto end;
+ }
+ ret = lseek(fd, length, SEEK_SET);
+ if (ret < 0) {
+ PERROR("lseek");
+ goto end;
+ }
+end:
+ return ret;
+}
+
+static const char *get_man_bin_path(void)
+{
+ char *env_man_path = lttng_secure_getenv(DEFAULT_MAN_BIN_PATH_ENV);
+
+ if (env_man_path) {
+ return env_man_path;
+ }
+
+ return DEFAULT_MAN_BIN_PATH;
+}
+
+LTTNG_HIDDEN
+int utils_show_man_page(int section, const char *page_name)
+{
+ char section_string[8];
+ const char *man_bin_path = get_man_bin_path();
+ int ret;
+
+ /* Section integer -> section string */
+ ret = sprintf(section_string, "%d", section);
+ assert(ret > 0 && ret < 8);
+
+ /*
+ * Execute man pager.
+ *
+ * We provide --manpath to man here because LTTng-tools can
+ * be installed outside /usr, in which case its man pages are
+ * not located in the default /usr/share/man directory.
+ */
+ ret = execlp(man_bin_path, "man", "--manpath", MANPATH,
+ section_string, page_name, NULL);
+ return ret;
+}