/*
* 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 <grp.h>
+#include <pwd.h>
+#include <sys/file.h>
+#include <unistd.h>
#include <common/common.h>
+#include <common/readwrite.h>
+#include <common/runas.h>
+#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"
+#include "defaults.h"
+#include "time.h"
+
+#define PROC_MEMINFO_PATH "/proc/meminfo"
+#define PROC_MEMINFO_MEMAVAILABLE_LINE "MemAvailable:"
+#define PROC_MEMINFO_MEMTOTAL_LINE "MemTotal:"
+
+/* The length of the longest field of `/proc/meminfo`. */
+#define PROC_MEMINFO_FIELD_MAX_NAME_LEN 20
+
+#if (PROC_MEMINFO_FIELD_MAX_NAME_LEN == 20)
+#define MAX_NAME_LEN_SCANF_IS_A_BROKEN_API "19"
+#else
+#error MAX_NAME_LEN_SCANF_IS_A_BROKEN_API must be updated to match (PROC_MEMINFO_FIELD_MAX_NAME_LEN - 1)
+#endif
/*
- * 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.
+ * 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.
*/
-char *utils_expand_path(const char *path)
+LTTNG_HIDDEN
+char *utils_partial_realpath(const char *path, char *resolved_path, size_t size)
{
- const char *end_path = path;
- char *next, *cut_path = NULL, *expanded_path = NULL;
+ char *cut_path = NULL, *try_path = NULL, *try_path_prev = NULL;
+ const char *next, *prev, *end;
/* Safety net */
if (path == NULL) {
goto error;
}
- /* Find last token delimited by '/' */
- while ((next = strpbrk(end_path + 1, "/"))) {
- end_path = next;
+ /*
+ * 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--;
}
- /* Cut last token from original path */
- cut_path = strndup(path, end_path - 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;
- expanded_path = zmalloc(PATH_MAX);
- if (expanded_path == NULL) {
- PERROR("zmalloc expand path");
+ /* 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
+ */
+ 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_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, 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
+ * 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 */
+ 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) {
+ 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);
+ free(try_path);
+ if (try_path_prev != try_path) {
+ free(try_path_prev);
+ }
+ return NULL;
+}
+
+static
+int expand_double_slashes_dot_and_dotdot(char *path)
+{
+ size_t expanded_path_len, path_len;
+ const char *curr_char, *path_last_char, *next_slash, *prev_slash;
+
+ path_len = strlen(path);
+ path_last_char = &path[path_len];
+
+ if (path_len == 0) {
goto error;
}
- 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);
+ expanded_path_len = 0;
+
+ /* We iterate over the provided path to expand the "//", "../" and "./" */
+ for (curr_char = path; curr_char <= path_last_char; curr_char = next_slash + 1) {
+ /* Find the next forward slash. */
+ size_t curr_token_len;
+
+ if (curr_char == path_last_char) {
+ expanded_path_len++;
+ break;
+ }
+
+ next_slash = memchr(curr_char, '/', path_last_char - curr_char);
+ if (next_slash == NULL) {
+ /* Reached the end of the provided path. */
+ next_slash = path_last_char;
+ }
+
+ /* Compute how long is the previous token. */
+ curr_token_len = next_slash - curr_char;
+ switch(curr_token_len) {
+ case 0:
+ /*
+ * The pointer has not move meaning that curr_char is
+ * pointing to a slash. It that case there is no token
+ * to copy, so continue the iteration to find the next
+ * token
+ */
+ continue;
+ case 1:
+ /*
+ * The pointer moved 1 character. Check if that
+ * character is a dot ('.'), if it is: omit it, else
+ * copy the token to the normalized path.
+ */
+ if (curr_char[0] == '.') {
+ continue;
+ }
+ break;
+ case 2:
+ /*
+ * The pointer moved 2 characters. Check if these
+ * characters are double dots ('..'). If that is the
+ * case, we need to remove the last token of the
+ * normalized path.
+ */
+ if (curr_char[0] == '.' && curr_char[1] == '.') {
+ /*
+ * Find the previous path component by
+ * using the memrchr function to find the
+ * previous forward slash and substract that
+ * len to the resulting path.
+ */
+ prev_slash = lttng_memrchr(path, '/', expanded_path_len);
+ /*
+ * If prev_slash is NULL, we reached the
+ * beginning of the path. We can't go back any
+ * further.
+ */
+ if (prev_slash != NULL) {
+ expanded_path_len = prev_slash - path;
+ }
+ continue;
+ }
break;
default:
- PERROR("realpath utils expand path");
break;
}
+
+ /*
+ * Copy the current token which is neither a '.' nor a '..'.
+ */
+ path[expanded_path_len++] = '/';
+ memcpy(&path[expanded_path_len], curr_char, curr_token_len);
+ expanded_path_len += curr_token_len;
+ }
+
+ if (expanded_path_len == 0) {
+ path[expanded_path_len++] = '/';
+ }
+
+ path[expanded_path_len] = '\0';
+ return 0;
+error:
+ return -1;
+}
+
+/*
+ * 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, bool keep_symlink)
+{
+ int ret;
+ char *absolute_path = NULL;
+ char *last_token;
+ bool is_dot, is_dotdot;
+
+ /* Safety net */
+ if (path == NULL) {
+ goto error;
+ }
+
+ /* Allocate memory for the absolute_path */
+ absolute_path = zmalloc(LTTNG_PATH_MAX);
+ if (absolute_path == NULL) {
+ PERROR("zmalloc expand path");
+ goto error;
+ }
+
+ if (path[0] == '/') {
+ ret = lttng_strncpy(absolute_path, path, LTTNG_PATH_MAX);
+ if (ret) {
+ ERR("Path exceeds maximal size of %i bytes", LTTNG_PATH_MAX);
+ goto error;
+ }
+ } else {
+ /*
+ * This is a relative path. We need to get the present working
+ * directory and start the path walk from there.
+ */
+ char current_working_dir[LTTNG_PATH_MAX];
+ char *cwd_ret;
+
+ cwd_ret = getcwd(current_working_dir, sizeof(current_working_dir));
+ if (!cwd_ret) {
+ goto error;
+ }
+ /*
+ * Get the number of character in the CWD and allocate an array
+ * to can hold it and the path provided by the caller.
+ */
+ ret = snprintf(absolute_path, LTTNG_PATH_MAX, "%s/%s",
+ current_working_dir, path);
+ if (ret >= LTTNG_PATH_MAX) {
+ ERR("Concatenating current working directory %s and path %s exceeds maximal size of %i bytes",
+ current_working_dir, path, LTTNG_PATH_MAX);
+ goto error;
+ }
+ }
+
+ if (keep_symlink) {
+ /* Resolve partially our path */
+ absolute_path = utils_partial_realpath(absolute_path,
+ absolute_path, LTTNG_PATH_MAX);
+ }
+
+ ret = expand_double_slashes_dot_and_dotdot(absolute_path);
+ if (ret) {
goto error;
}
- /* Add end part to expanded path */
- strncat(expanded_path, end_path, PATH_MAX);
+ /* Identify the last token */
+ last_token = strrchr(absolute_path, '/');
- free(cut_path);
- return expanded_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(expanded_path);
- free(cut_path);
+ free(absolute_path);
return NULL;
}
+LTTNG_HIDDEN
+char *utils_expand_path(const char *path)
+{
+ return _utils_expand_path(path, true);
+}
+LTTNG_HIDDEN
+char *utils_expand_path_keep_symlink(const char *path)
+{
+ return _utils_expand_path(path, false);
+}
/*
* Create a pipe in dst.
*/
+LTTNG_HIDDEN
int utils_create_pipe(int *dst)
{
int ret;
* 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;
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;
/*
* Create a new string using two strings range.
*/
+LTTNG_HIDDEN
char *utils_strdupdelim(const char *begin, const char *end)
{
char *str;
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", (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);
+ fd = -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;
+ }
+
+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;
+ struct lttng_directory_handle handle;
+ const struct lttng_credentials creds = {
+ .uid = (uid_t) uid,
+ .gid = (gid_t) gid,
+ };
+
+ ret = lttng_directory_handle_init(&handle, NULL);
+ if (ret) {
+ goto end;
+ }
+ 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;
+}
+
+/*
+ * 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;
+ struct lttng_directory_handle handle;
+ const struct lttng_credentials creds = {
+ .uid = (uid_t) uid,
+ .gid = (gid_t) gid,
+ };
+
+ ret = lttng_directory_handle_init(&handle, NULL);
+ if (ret) {
+ goto end;
+ }
+ 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;
+}
+
+/*
+ * out_stream_path is the output parameter.
+ *
+ * Return 0 on success or else a negative value.
+ */
+LTTNG_HIDDEN
+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 count_str[MAX_INT_DEC_LEN(count) + 1] = {};
+ const char *path_separator;
+
+ if (path_name && path_name[strlen(path_name) - 1] == '/') {
+ path_separator = "";
+ } else {
+ path_separator = "/";
+ }
+
+ 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));
+ }
+
+ 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 {
+ ret = 0;
+ }
+ 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[LTTNG_PATH_MAX];
+
+ ret = utils_stream_file_path(path_name, file_name,
+ size, count, suffix, path, sizeof(path));
+ 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);
+ }
+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[LTTNG_PATH_MAX];
+
+ ret = utils_stream_file_path(path_name, file_name, size, count, suffix,
+ path, sizeof(path));
+ 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(stream_fd);
+
+ ret = close(out_fd);
+ if (ret < 0) {
+ PERROR("Closing tracefile");
+ goto error;
+ }
+ *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;
+ }
+ } else {
+ if (new_count) {
+ (*new_count)++;
+ }
+ }
+
+ 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'.
+ *
+ * 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;
+}
+
+/**
+ * Parse a string that represents a time in human readable format. It
+ * supports decimal integers suffixed by:
+ * "us" for microsecond,
+ * "ms" for millisecond,
+ * "s" for second,
+ * "m" for minute,
+ * "h" for hour
+ *
+ * The suffix multiply the integer by:
+ * "us" : 1
+ * "ms" : 1000
+ * "s" : 1000000
+ * "m" : 60000000
+ * "h" : 3600000000
+ *
+ * Note that unit-less numbers are assumed to be microseconds.
+ *
+ * @param str The string to parse, assumed to be NULL-terminated.
+ * @param time_us Pointer to a uint64_t that will be filled with the
+ * resulting time in microseconds.
+ *
+ * @return 0 on success, -1 on failure.
+ */
+LTTNG_HIDDEN
+int utils_parse_time_suffix(char const * const str, uint64_t * const time_us)
+{
+ int ret;
+ uint64_t base_time;
+ uint64_t multiplier = 1;
+ const char *str_end;
+ char *num_end;
+
+ if (!str) {
+ DBG("utils_parse_time_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_time_suffix: invalid time string, should not contain '-'.");
+ ret = -1;
+ goto end;
+ }
+
+ /* str_end will point to the \0 */
+ str_end = str + strlen(str);
+ errno = 0;
+ base_time = strtoull(str, &num_end, 10);
+ if (errno != 0) {
+ PERROR("utils_parse_time_suffix strtoull on string \"%s\"", str);
+ ret = -1;
+ goto end;
+ }
+
+ if (num_end == str) {
+ /* strtoull parsed nothing, not good. */
+ DBG("utils_parse_time_suffix: strtoull had nothing good to parse.");
+ ret = -1;
+ goto end;
+ }
+
+ /* Check if a prefix is present. */
+ switch (*num_end) {
+ case 'u':
+ /*
+ * Microsecond (us)
+ *
+ * Skip the "us" if the string matches the "us" suffix,
+ * otherwise let the check for the end of the string handle
+ * the error reporting.
+ */
+ if (*(num_end + 1) == 's') {
+ num_end += 2;
+ }
+ break;
+ case 'm':
+ if (*(num_end + 1) == 's') {
+ /* Millisecond (ms) */
+ multiplier = USEC_PER_MSEC;
+ /* Skip the 's' */
+ num_end++;
+ } else {
+ /* Minute (m) */
+ multiplier = USEC_PER_MINUTE;
+ }
+ num_end++;
+ break;
+ case 's':
+ /* Second */
+ multiplier = USEC_PER_SEC;
+ num_end++;
+ break;
+ case 'h':
+ /* Hour */
+ multiplier = USEC_PER_HOURS;
+ num_end++;
+ break;
+ case '\0':
+ break;
+ default:
+ DBG("utils_parse_time_suffix: invalid suffix.");
+ ret = -1;
+ goto end;
+ }
+
+ /* Check for garbage after the valid input. */
+ if (num_end != str_end) {
+ DBG("utils_parse_time_suffix: Garbage after time string.");
+ ret = -1;
+ goto end;
+ }
+
+ *time_us = base_time * multiplier;
+
+ /* Check for overflow */
+ if ((*time_us / multiplier) != base_time) {
+ DBG("utils_parse_time_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
+
+#if defined(__x86_64)
+static inline
+unsigned int fls_u64(uint64_t x)
+{
+ long r;
+
+ asm("bsrq %1,%0\n\t"
+ "jnz 1f\n\t"
+ "movq $-1,%0\n\t"
+ "1:\n\t"
+ : "=r" (r) : "rm" (x));
+ return r + 1;
+}
+#define HAS_FLS_U64
+#endif
+
+#ifndef HAS_FLS_U64
+static __attribute__((unused))
+unsigned int fls_u64(uint64_t x)
+{
+ unsigned int r = 64;
+
+ if (!x)
+ return 0;
+
+ if (!(x & 0xFFFFFFFF00000000ULL)) {
+ x <<= 32;
+ r -= 32;
+ }
+ if (!(x & 0xFFFF000000000000ULL)) {
+ x <<= 16;
+ r -= 16;
+ }
+ if (!(x & 0xFF00000000000000ULL)) {
+ x <<= 8;
+ r -= 8;
+ }
+ if (!(x & 0xF000000000000000ULL)) {
+ x <<= 4;
+ r -= 4;
+ }
+ if (!(x & 0xC000000000000000ULL)) {
+ x <<= 2;
+ r -= 2;
+ }
+ if (!(x & 0x8000000000000000ULL)) {
+ x <<= 1;
+ r -= 1;
+ }
+ return r;
+}
+#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);
+}
+
+/*
+ * Return the minimum order for which x <= (1UL << order).
+ * Return -1 if x is 0.
+ */
+LTTNG_HIDDEN
+int utils_get_count_order_u64(uint64_t x)
+{
+ if (!x) {
+ return -1;
+ }
+
+ return fls_u64(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;
+}
+
+/*
+ * 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 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
+int utils_get_group_id(const char *name, bool warn, gid_t *gid)
+{
+ 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;
+ }
+
+ 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;
+ }
+
+ 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;
+ }
+
+ 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;
+ }
+ lttng_dynamic_buffer_reset(&buffer);
+ return ret;
+}
+
+/*
+ * 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)
+{
+ int ret;
+ struct lttng_directory_handle handle;
+
+ 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:
+ return ret;
+}
+
+LTTNG_HIDDEN
+int utils_truncate_stream_file(int fd, off_t length)
+{
+ int ret;
+ off_t lseek_ret;
+
+ ret = ftruncate(fd, length);
+ if (ret < 0) {
+ PERROR("ftruncate");
+ goto end;
+ }
+ lseek_ret = lseek(fd, length, SEEK_SET);
+ if (lseek_ret < 0) {
+ PERROR("lseek");
+ ret = -1;
+ 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_help(int section, const char *page_name,
+ const char *help_msg)
+{
+ char section_string[8];
+ const char *man_bin_path = get_man_bin_path();
+ int ret = 0;
+
+ if (help_msg) {
+ printf("%s", help_msg);
+ goto end;
+ }
+
+ /* Section integer -> section string */
+ ret = sprintf(section_string, "%d", section);
+ assert(ret > 0 && ret < 8);
+
+ /*
+ * Execute man pager.
+ *
+ * We provide -M 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", "-M", MANPATH,
+ section_string, page_name, NULL);
+
+end:
+ return ret;
+}
+
+static
+int read_proc_meminfo_field(const char *field, size_t *value)
+{
+ int ret;
+ FILE *proc_meminfo;
+ char name[PROC_MEMINFO_FIELD_MAX_NAME_LEN] = {};
+
+ proc_meminfo = fopen(PROC_MEMINFO_PATH, "r");
+ if (!proc_meminfo) {
+ PERROR("Failed to fopen() " PROC_MEMINFO_PATH);
+ ret = -1;
+ goto fopen_error;
+ }
+
+ /*
+ * Read the contents of /proc/meminfo line by line to find the right
+ * field.
+ */
+ while (!feof(proc_meminfo)) {
+ unsigned long value_kb;
+
+ ret = fscanf(proc_meminfo,
+ "%" MAX_NAME_LEN_SCANF_IS_A_BROKEN_API "s %lu kB\n",
+ name, &value_kb);
+ if (ret == EOF) {
+ /*
+ * fscanf() returning EOF can indicate EOF or an error.
+ */
+ if (ferror(proc_meminfo)) {
+ PERROR("Failed to parse " PROC_MEMINFO_PATH);
+ }
+ break;
+ }
+
+ if (ret == 2 && strcmp(name, field) == 0) {
+ /*
+ * This number is displayed in kilo-bytes. Return the
+ * number of bytes.
+ */
+ *value = ((size_t) value_kb) * 1024;
+ ret = 0;
+ goto found;
+ }
+ }
+ /* Reached the end of the file without finding the right field. */
+ ret = -1;
+
+found:
+ fclose(proc_meminfo);
+fopen_error:
+ return ret;
+}
+
+/*
+ * Returns an estimate of the number of bytes of memory available based on the
+ * the information in `/proc/meminfo`. The number returned by this function is
+ * a best guess.
+ */
+LTTNG_HIDDEN
+int utils_get_memory_available(size_t *value)
+{
+ return read_proc_meminfo_field(PROC_MEMINFO_MEMAVAILABLE_LINE, value);
+}
+
+/*
+ * Returns the total size of the memory on the system in bytes based on the
+ * the information in `/proc/meminfo`.
+ */
+LTTNG_HIDDEN
+int utils_get_memory_total(size_t *value)
+{
+ return read_proc_meminfo_field(PROC_MEMINFO_MEMTOTAL_LINE, value);
+}
projects / lttng-tools.git / blobdiff