#include <common/compat/getenv.h>
#include <common/compat/string.h>
#include <common/compat/dirent.h>
+#include <common/compat/directory-handle.h>
+#include <common/dynamic-buffer.h>
+#include <common/string-utils/format.h>
#include <lttng/constant.h>
#include "utils.h"
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;
-}
-
/*
* Create directory using the given path and mode.
*
int utils_mkdir(const char *path, mode_t mode, int uid, int gid)
{
int ret;
+ struct lttng_directory_handle handle;
+ const struct lttng_credentials creds = {
+ .uid = (uid_t) uid,
+ .gid = (gid_t) gid,
+ };
- 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;
- int ret;
-
- assert(path);
-
- ret = snprintf(tmp, sizeof(tmp), "%s", path);
- if (ret < 0) {
- PERROR("snprintf mkdir");
- goto error;
- }
-
- len = ret;
- if (tmp[len - 1] == '/') {
- tmp[len - 1] = 0;
- }
-
- for (p = tmp + 1; *p; p++) {
- if (*p == '/') {
- *p = 0;
- if (tmp[strlen(tmp) - 1] == '.' &&
- tmp[strlen(tmp) - 2] == '.' &&
- tmp[strlen(tmp) - 3] == '/') {
- ERR("Using '/../' is not permitted in the trace path (%s)",
- tmp);
- ret = -1;
- goto error;
- }
- ret = mkdir_check_exists(tmp, mode);
- if (ret < 0) {
- if (errno != EACCES) {
- PERROR("mkdir recursive");
- ret = -errno;
- goto error;
- }
- }
- *p = '/';
- }
- }
-
- ret = mkdir_check_exists(tmp, mode);
- if (ret < 0) {
- PERROR("mkdir recursive last element");
- ret = -errno;
+ ret = lttng_directory_handle_init(&handle, NULL);
+ if (ret) {
+ goto end;
}
-
-error:
+ ret = lttng_directory_handle_create_subdirectory_as_user(
+ &handle, path, mode,
+ (uid >= 0 || gid >= 0) ? &creds : NULL);
+ lttng_directory_handle_fini(&handle);
+end:
return ret;
}
int utils_mkdir_recursive(const char *path, mode_t mode, int uid, int gid)
{
int ret;
+ struct lttng_directory_handle handle;
+ const struct lttng_credentials creds = {
+ .uid = (uid_t) uid,
+ .gid = (gid_t) gid,
+ };
- 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 (ret < 0) {
- PERROR("snprintf create output file");
- goto error;
- }
-
- /* Setup extra string if suffix or/and a count is needed. */
- if (size > 0 && suffix) {
- ret = asprintf(&extra, "_%" PRIu64 "%s", count, suffix);
- } else if (size > 0) {
- ret = asprintf(&extra, "_%" PRIu64, count);
- } else if (suffix) {
- ret = asprintf(&extra, "%s", suffix);
- }
- if (ret < 0) {
- PERROR("Allocating extra string to name");
- goto error;
- }
-
- /*
- * 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);
- if (ret < 0) {
- PERROR("Allocating path name with extra string");
- goto error_free_suffix;
- }
- strncpy(path, path_name_suffix, PATH_MAX - 1);
- path[PATH_MAX - 1] = '\0';
- } else {
- ret = lttng_strncpy(path, full_path, PATH_MAX);
- if (ret) {
- ERR("Failed to copy stream file name");
- goto error_free_suffix;
- }
- }
- 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;
- }
-
- /*
- * With the session rotation feature on the relay, we might need to seek
- * and truncate a tracefile, so we need read and write access.
- */
- flags = O_RDWR | O_CREAT | O_TRUNC;
- /* Open with 660 mode */
- mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP;
-
- if (uid < 0 || gid < 0) {
- ret = open(path, flags, mode);
- } else {
- ret = run_as_open(path, flags, mode, uid, gid);
- }
- if (ret < 0) {
- PERROR("open stream path %s", path);
+ ret = lttng_directory_handle_init(&handle, NULL);
+ if (ret) {
+ goto end;
}
-error:
+ ret = lttng_directory_handle_create_subdirectory_recursive_as_user(
+ &handle, path, mode,
+ (uid >= 0 || gid >= 0) ? &creds : NULL);
+ lttng_directory_handle_fini(&handle);
+end:
return ret;
}
/*
- * Unlink the stream tracefile from disk.
+ * out_stream_path is the output parameter.
*
* 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 utils_stream_file_path(const char *path_name, const char *file_name,
+ uint64_t size, uint64_t count, const char *suffix,
+ char *out_stream_path, size_t stream_path_len)
{
int ret;
- char path[PATH_MAX];
+ char count_str[MAX_INT_DEC_LEN(count) + 1] = {};
+ const char *path_separator;
- 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);
+ if (path_name && path_name[strlen(path_name) - 1] == '/') {
+ path_separator = "";
} else {
- ret = run_as_unlink(path, uid, gid);
- }
- if (ret < 0) {
- goto error;
+ path_separator = "/";
}
-error:
- DBG("utils_unlink_stream_file %s returns %d", path, ret);
- return ret;
-}
-/*
- * Change the output tracefile according to the given size and count The
- * new_count pointer is set during this operation.
- *
- * From the consumer, the stream lock MUST be held before calling this function
- * because we are modifying the stream status.
- *
- * Return 0 on success or else a negative value.
- */
-LTTNG_HIDDEN
-int utils_rotate_stream_file(char *path_name, char *file_name, uint64_t size,
- uint64_t count, int uid, int gid, int out_fd, uint64_t *new_count,
- int *stream_fd)
-{
- int ret;
-
- assert(stream_fd);
-
- ret = close(out_fd);
- if (ret < 0) {
- PERROR("Closing tracefile");
- goto error;
+ path_name = path_name ? : "";
+ suffix = suffix ? : "";
+ if (size > 0) {
+ ret = snprintf(count_str, sizeof(count_str), "_%" PRIu64,
+ count);
+ assert(ret > 0 && ret < sizeof(count_str));
}
- *stream_fd = -1;
- 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.
- */
- 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;
- }
+ ret = snprintf(out_stream_path, stream_path_len, "%s%s%s%s%s",
+ path_name, path_separator, file_name, count_str,
+ suffix);
+ if (ret < 0 || ret >= stream_path_len) {
+ ERR("Truncation occurred while formatting stream path");
+ ret = -1;
} else {
- if (new_count) {
- (*new_count)++;
- }
+ ret = 0;
}
-
- ret = utils_create_stream_file(path_name, file_name, size,
- new_count ? *new_count : 0, uid, gid, 0);
- if (ret < 0) {
- goto error;
- }
- *stream_fd = ret;
-
- /* Success. */
- ret = 0;
-
-error:
return ret;
}
-
/**
* Parse a string that represents a size in human readable format. It
* supports decimal integers suffixed by 'k', 'K', 'M' or 'G'.
* Otherwise returns the value of HOME.
*/
LTTNG_HIDDEN
-char *utils_get_home_dir(void)
+const char *utils_get_home_dir(void)
{
char *val = NULL;
struct passwd *pwd;
}
/*
- * Return the group ID matching name, else 0 if it cannot be found.
+ * Return 0 on success and set *gid to the group_ID matching the passed name.
+ * Else -1 if it cannot be found or an error occurred.
*/
LTTNG_HIDDEN
-gid_t utils_get_group_id(const char *name)
+int utils_get_group_id(const char *name, bool warn, gid_t *gid)
{
- struct group *grp;
+ static volatile int warn_once;
+ int ret;
+ long sys_len;
+ size_t len;
+ struct group grp;
+ struct group *result;
+ struct lttng_dynamic_buffer buffer;
+
+ /* Get the system limit, if it exists. */
+ sys_len = sysconf(_SC_GETGR_R_SIZE_MAX);
+ if (sys_len == -1) {
+ len = 1024;
+ } else {
+ len = (size_t) sys_len;
+ }
- grp = getgrnam(name);
- if (!grp) {
- static volatile int warn_once;
+ lttng_dynamic_buffer_init(&buffer);
+ ret = lttng_dynamic_buffer_set_size(&buffer, len);
+ if (ret) {
+ ERR("Failed to allocate group info buffer");
+ ret = -1;
+ goto error;
+ }
- if (!warn_once) {
- WARN("No tracing group detected");
- warn_once = 1;
+ while ((ret = getgrnam_r(name, &grp, buffer.data, buffer.size, &result)) == ERANGE) {
+ const size_t new_len = 2 * buffer.size;
+
+ /* Buffer is not big enough, increase its size. */
+ if (new_len < buffer.size) {
+ ERR("Group info buffer size overflow");
+ ret = -1;
+ goto error;
}
- return 0;
+
+ ret = lttng_dynamic_buffer_set_size(&buffer, new_len);
+ if (ret) {
+ ERR("Failed to grow group info buffer to %zu bytes",
+ new_len);
+ ret = -1;
+ goto error;
+ }
+ }
+ if (ret) {
+ PERROR("Failed to get group file entry for group name \"%s\"",
+ name);
+ ret = -1;
+ goto error;
+ }
+
+ /* Group not found. */
+ if (!result) {
+ ret = -1;
+ goto error;
+ }
+
+ *gid = result->gr_gid;
+ ret = 0;
+
+error:
+ if (ret && warn && !warn_once) {
+ WARN("No tracing group detected");
+ warn_once = 1;
}
- return grp->gr_gid;
+ lttng_dynamic_buffer_reset(&buffer);
+ return ret;
}
/*
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;
- }
+ int ret;
+ struct lttng_directory_handle handle;
- 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;
- }
+ ret = lttng_directory_handle_init(&handle, NULL);
+ if (ret) {
+ goto end;
}
+ ret = lttng_directory_handle_remove_subdirectory(&handle, path);
+ lttng_directory_handle_fini(&handle);
end:
- closeret = closedir(dir);
- if (closeret) {
- PERROR("closedir");
- }
- if (is_empty) {
- DBG3("Attempting rmdir %s", path);
- ret = rmdir(path);
- }
return ret;
}