+++ /dev/null
-/*
- * 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
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 51
- * 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 <sys/stat.h>
-#include <sys/types.h>
-#include <unistd.h>
-#include <inttypes.h>
-#include <grp.h>
-#include <pwd.h>
-#include <sys/file.h>
-#include <dirent.h>
-
-#include <common/common.h>
-#include <common/runas.h>
-#include <common/compat/getenv.h>
-#include <common/compat/string.h>
-
-#include "utils.h"
-#include "defaults.h"
-
-/*
- * 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_partial_realpath(const char *path, char *resolved_path, size_t size)
-{
- char *cut_path = NULL, *try_path = NULL, *try_path_prev = NULL;
- const char *next, *prev, *end;
-
- /* Safety net */
- if (path == NULL) {
- 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--;
- }
-
- /* 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;
-
- /* 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;
- }
-
- /* Cut the part we will be trying to resolve */
- cut_path = lttng_strndup(path, next - path);
- if (cut_path == NULL) {
- PERROR("lttng_strndup");
- goto error;
- }
-
- /* 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 the allocated memory */
- free(cut_path);
- cut_path = NULL;
- }
-
- /* 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;
- }
- }
-
- /*
- * 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';
- }
-
- /*
- * Duplicate the memory used by prev in case resolved_path and
- * 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
- */
- } else {
- strncpy(resolved_path, path, size);
- }
-
- /* Then we return the 'partially' resolved path */
- return resolved_path;
-
-error:
- free(resolved_path);
- free(cut_path);
- return NULL;
-}
-
-/*
- * 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)
-{
- 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 absolute_path */
- absolute_path = zmalloc(PATH_MAX);
- if (absolute_path == NULL) {
- PERROR("zmalloc expand path");
- goto error;
- }
-
- /*
- * 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 {
- strncpy(absolute_path, path, PATH_MAX);
- }
-
- /* Resolve partially our path */
- absolute_path = utils_partial_realpath(absolute_path,
- absolute_path, PATH_MAX);
-
- /* As long as we find '/./' in the working_path string */
- while ((next = strstr(absolute_path, "/./"))) {
-
- /* We prepare the start_path not containing it */
- 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);
-
- free(start_path);
- }
-
- /* 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 = 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);
-
- /* 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);
- }
-
- /* 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:
- free(absolute_path);
- return NULL;
-}
-
-/*
- * Create a pipe in dst.
- */
-LTTNG_HIDDEN
-int utils_create_pipe(int *dst)
-{
- int ret;
-
- if (dst == NULL) {
- return -1;
- }
-
- ret = pipe(dst);
- if (ret < 0) {
- PERROR("create pipe");
- }
-
- return ret;
-}
-
-/*
- * Create pipe and set CLOEXEC flag to both fd.
- *
- * Make sure the pipe opened by this function are closed at some point. Use
- * utils_close_pipe().
- */
-LTTNG_HIDDEN
-int utils_create_pipe_cloexec(int *dst)
-{
- int ret, i;
-
- if (dst == NULL) {
- return -1;
- }
-
- ret = utils_create_pipe(dst);
- if (ret < 0) {
- goto error;
- }
-
- for (i = 0; i < 2; i++) {
- ret = fcntl(dst[i], F_SETFD, FD_CLOEXEC);
- if (ret < 0) {
- PERROR("fcntl pipe cloexec");
- goto error;
- }
- }
-
-error:
- return ret;
-}
-
-/*
- * Create pipe and set fd flags to FD_CLOEXEC and O_NONBLOCK.
- *
- * Make sure the pipe opened by this function are closed at some point. Use
- * utils_close_pipe(). Using pipe() and fcntl rather than pipe2() to
- * support OSes other than Linux 2.6.23+.
- */
-LTTNG_HIDDEN
-int utils_create_pipe_cloexec_nonblock(int *dst)
-{
- int ret, i;
-
- if (dst == NULL) {
- return -1;
- }
-
- ret = utils_create_pipe(dst);
- if (ret < 0) {
- goto error;
- }
-
- for (i = 0; i < 2; i++) {
- ret = fcntl(dst[i], F_SETFD, FD_CLOEXEC);
- if (ret < 0) {
- PERROR("fcntl pipe cloexec");
- goto error;
- }
- /*
- * Note: we override any flag that could have been
- * previously set on the fd.
- */
- ret = fcntl(dst[i], F_SETFL, O_NONBLOCK);
- if (ret < 0) {
- PERROR("fcntl pipe nonblock");
- goto error;
- }
- }
-
-error:
- return ret;
-}
-
-/*
- * Close both read and write side of the pipe.
- */
-LTTNG_HIDDEN
-void utils_close_pipe(int *src)
-{
- int i, ret;
-
- if (src == NULL) {
- return;
- }
-
- for (i = 0; i < 2; i++) {
- /* Safety check */
- if (src[i] < 0) {
- continue;
- }
-
- ret = close(src[i]);
- if (ret) {
- PERROR("close pipe");
- }
- }
-}
-
-/*
- * Create a new string using two strings range.
- */
-LTTNG_HIDDEN
-char *utils_strdupdelim(const char *begin, const char *end)
-{
- char *str;
-
- str = zmalloc(end - begin + 1);
- if (str == NULL) {
- PERROR("zmalloc strdupdelim");
- goto error;
- }
-
- memcpy(str, begin, end - begin);
- str[end - begin] = '\0';
-
-error:
- return str;
-}
-
-/*
- * Set CLOEXEC flag to the give file descriptor.
- */
-LTTNG_HIDDEN
-int utils_set_fd_cloexec(int fd)
-{
- int ret;
-
- if (fd < 0) {
- ret = -EINVAL;
- goto end;
- }
-
- ret = fcntl(fd, F_SETFD, FD_CLOEXEC);
- if (ret < 0) {
- PERROR("fcntl cloexec");
- ret = -errno;
- }
-
-end:
- return ret;
-}
-
-/*
- * Create pid file to the given path and filename.
- */
-LTTNG_HIDDEN
-int utils_create_pid_file(pid_t pid, const char *filepath)
-{
- int ret;
- FILE *fp;
-
- assert(filepath);
-
- fp = fopen(filepath, "w");
- if (fp == NULL) {
- PERROR("open pid file %s", filepath);
- ret = -1;
- goto error;
- }
-
- ret = fprintf(fp, "%d\n", pid);
- if (ret < 0) {
- PERROR("fprintf pid file");
- goto error;
- }
-
- if (fclose(fp)) {
- PERROR("fclose");
- }
- DBG("Pid %d written in file %s", 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;
-
- assert(filepath);
-
- 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.
- */
- ret = flock(fd, LOCK_EX | LOCK_NB);
- if (ret) {
- ERR("Could not get lock file %s, another instance is running.",
- filepath);
- if (close(fd)) {
- PERROR("close lock file");
- }
- fd = ret;
- goto error;
- }
-
-error:
- return fd;
-}
-
-/*
- * Create directory using the given path and mode.
- *
- * On success, return 0 else a negative error code.
- */
-LTTNG_HIDDEN
-int utils_mkdir(const char *path, mode_t mode, int uid, int gid)
-{
- int ret;
-
- if (uid < 0 || gid < 0) {
- ret = mkdir(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(tmp, mode);
- if (ret < 0) {
- if (errno != EEXIST) {
- PERROR("mkdir recursive");
- ret = -errno;
- goto error;
- }
- }
- *p = '/';
- }
- }
-
- ret = mkdir(tmp, mode);
- if (ret < 0) {
- if (errno != EEXIST) {
- PERROR("mkdir recursive last element");
- ret = -errno;
- } else {
- ret = 0;
- }
- }
-
-error:
- return ret;
-}
-
-/*
- * Recursively create directory using the given path and mode, under the
- * provided uid and gid.
- *
- * On success, return 0 else a negative error code.
- */
-LTTNG_HIDDEN
-int utils_mkdir_recursive(const char *path, mode_t mode, int uid, int gid)
-{
- int ret;
-
- 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 {
- 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;
- /* 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);
- }
-error:
- return ret;
-}
-
-/*
- * 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;
-}
-
-/*
- * 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(new_count);
- assert(stream_fd);
-
- ret = close(out_fd);
- if (ret < 0) {
- PERROR("Closing tracefile");
- goto error;
- }
-
- 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)++;
- }
-
- ret = utils_create_stream_file(path_name, file_name, size, *new_count,
- 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'.
- *
- * The suffix multiply the integer by:
- * 'k': 1024
- * 'M': 1024^2
- * 'G': 1024^3
- *
- * @param str The string to parse.
- * @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(const char * const str, uint64_t * const size)
-{
- int ret;
- uint64_t base_size;
- long shift = 0;
- const char *str_end;
- char *num_end;
-
- if (!str) {
- DBG("utils_parse_size_suffix: received a NULL string.");
- ret = -1;
- goto end;
- }
-
- /* 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 end;
- }
-
- /* str_end will point to the \0 */
- str_end = str + strlen(str);
- errno = 0;
- base_size = strtoull(str, &num_end, 0);
- if (errno != 0) {
- PERROR("utils_parse_size_suffix strtoull");
- ret = -1;
- goto end;
- }
-
- 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) {
- DBG("utils_parse_size_suffix: oops, overflow detected.");
- ret = -1;
- goto end;
- }
-
- ret = 0;
-end:
- return ret;
-}
-
-/*
- * fls: returns the position of the most significant bit.
- * Returns 0 if no bit is set, else returns the position of the most
- * significant bit (from 1 to 32 on 32-bit, from 1 to 64 on 64-bit).
- */
-#if defined(__i386) || defined(__x86_64)
-static inline unsigned int fls_u32(uint32_t x)
-{
- int r;
-
- asm("bsrl %1,%0\n\t"
- "jnz 1f\n\t"
- "movl $-1,%0\n\t"
- "1:\n\t"
- : "=r" (r) : "rm" (x));
- return r + 1;
-}
-#define HAS_FLS_U32
-#endif
-
-#ifndef HAS_FLS_U32
-static __attribute__((unused)) unsigned int fls_u32(uint32_t x)
-{
- unsigned int r = 32;
-
- if (!x) {
- return 0;
- }
- if (!(x & 0xFFFF0000U)) {
- x <<= 16;
- r -= 16;
- }
- if (!(x & 0xFF000000U)) {
- x <<= 8;
- r -= 8;
- }
- if (!(x & 0xF0000000U)) {
- x <<= 4;
- r -= 4;
- }
- if (!(x & 0xC0000000U)) {
- x <<= 2;
- r -= 2;
- }
- if (!(x & 0x80000000U)) {
- x <<= 1;
- r -= 1;
- }
- return r;
-}
-#endif
-
-/*
- * Return the minimum order for which x <= (1UL << order).
- * Return -1 if x is 0.
- */
-LTTNG_HIDDEN
-int utils_get_count_order_u32(uint32_t x)
-{
- if (!x) {
- return -1;
- }
-
- return fls_u32(x - 1);
-}
-
-/**
- * Obtain the value of LTTNG_HOME environment variable, if exists.
- * Otherwise returns the value of HOME.
- */
-LTTNG_HIDDEN
-char *utils_get_home_dir(void)
-{
- char *val = NULL;
- 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) {
- goto end;
- }
-
- /* 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);
-}
-
-/*
- * With the given format, fill dst with the time of len maximum siz.
- *
- * Return amount of bytes set in the buffer or else 0 on error.
- */
-LTTNG_HIDDEN
-size_t utils_get_current_time_str(const char *format, char *dst, size_t len)
-{
- size_t ret;
- time_t rawtime;
- struct tm *timeinfo;
-
- assert(format);
- assert(dst);
-
- /* Get date and time for session path */
- time(&rawtime);
- timeinfo = localtime(&rawtime);
- ret = strftime(dst, len, format, timeinfo);
- if (ret == 0) {
- ERR("Unable to strftime with format %s at dst %p of len %zu", format,
- dst, len);
- }
-
- return ret;
-}
-
-/*
- * Return the group ID matching name, else 0 if it cannot be found.
- */
-LTTNG_HIDDEN
-gid_t utils_get_group_id(const char *name)
-{
- struct group *grp;
-
- grp = getgrnam(name);
- if (!grp) {
- static volatile int warn_once;
-
- if (!warn_once) {
- WARN("No tracing group detected");
- warn_once = 1;
- }
- return 0;
- }
- 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 = dirfd(dir);
- if (dir_fd < 0) {
- PERROR("dirfd");
- return -1;
- }
-
- path_len = strlen(path);
- while ((entry = readdir(dir))) {
- if (!strcmp(entry->d_name, ".")
- || !strcmp(entry->d_name, ".."))
- continue;
-
- struct stat st;
- size_t name_len;
- char filename[PATH_MAX];
-
- 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