2 * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
3 * Copyright (C) 2013 - Raphaël Beamonte <raphael.beamonte@gmail.com>
4 * Copyright (C) 2013 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License, version 2 only, as
8 * published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 51
17 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
27 #include <sys/types.h>
35 #include <common/common.h>
36 #include <common/runas.h>
37 #include <common/compat/getenv.h>
38 #include <common/compat/string.h>
39 #include <common/compat/dirent.h>
40 #include <lttng/constant.h>
46 * Return a partial realpath(3) of the path even if the full path does not
47 * exist. For instance, with /tmp/test1/test2/test3, if test2/ does not exist
48 * but the /tmp/test1 does, the real path for /tmp/test1 is concatened with
49 * /test2/test3 then returned. In normal time, realpath(3) fails if the end
50 * point directory does not exist.
51 * In case resolved_path is NULL, the string returned was allocated in the
52 * function and thus need to be freed by the caller. The size argument allows
53 * to specify the size of the resolved_path argument if given, or the size to
57 char *utils_partial_realpath(const char *path
, char *resolved_path
, size_t size
)
59 char *cut_path
= NULL
, *try_path
= NULL
, *try_path_prev
= NULL
;
60 const char *next
, *prev
, *end
;
68 * Identify the end of the path, we don't want to treat the
69 * last char if it is a '/', we will just keep it on the side
70 * to be added at the end, and return a value coherent with
71 * the path given as argument
73 end
= path
+ strlen(path
);
74 if (*(end
-1) == '/') {
78 /* Initiate the values of the pointers before looping */
81 /* Only to ensure try_path is not NULL to enter the while */
82 try_path
= (char *)next
;
84 /* Resolve the canonical path of the first part of the path */
85 while (try_path
!= NULL
&& next
!= end
) {
86 char *try_path_buf
= NULL
;
89 * If there is not any '/' left, we want to try with
92 next
= strpbrk(next
+ 1, "/");
97 /* Cut the part we will be trying to resolve */
98 cut_path
= lttng_strndup(path
, next
- path
);
99 if (cut_path
== NULL
) {
100 PERROR("lttng_strndup");
104 try_path_buf
= zmalloc(LTTNG_PATH_MAX
);
110 /* Try to resolve this part */
111 try_path
= realpath((char *) cut_path
, try_path_buf
);
112 if (try_path
== NULL
) {
115 * There was an error, we just want to be assured it
116 * is linked to an unexistent directory, if it's another
117 * reason, we spawn an error
121 /* Ignore the error */
124 PERROR("realpath (partial_realpath)");
129 /* Save the place we are before trying the next step */
132 try_path_prev
= try_path
;
136 /* Free the allocated memory */
141 /* Allocate memory for the resolved path if necessary */
142 if (resolved_path
== NULL
) {
143 resolved_path
= zmalloc(size
);
144 if (resolved_path
== NULL
) {
145 PERROR("zmalloc resolved path");
151 * If we were able to solve at least partially the path, we can concatenate
152 * what worked and what didn't work
154 if (try_path_prev
!= NULL
) {
155 /* If we risk to concatenate two '/', we remove one of them */
156 if (try_path_prev
[strlen(try_path_prev
) - 1] == '/' && prev
[0] == '/') {
157 try_path_prev
[strlen(try_path_prev
) - 1] = '\0';
161 * Duplicate the memory used by prev in case resolved_path and
162 * path are pointers for the same memory space
164 cut_path
= strdup(prev
);
165 if (cut_path
== NULL
) {
170 /* Concatenate the strings */
171 snprintf(resolved_path
, size
, "%s%s", try_path_prev
, cut_path
);
173 /* Free the allocated memory */
177 try_path_prev
= NULL
;
179 * Else, we just copy the path in our resolved_path to
183 strncpy(resolved_path
, path
, size
);
186 /* Then we return the 'partially' resolved path */
187 return resolved_path
;
193 if (try_path_prev
!= try_path
) {
200 int expand_double_slashes_dot_and_dotdot(char *path
)
202 size_t expanded_path_len
, path_len
;
203 const char *curr_char
, *path_last_char
, *next_slash
, *prev_slash
;
205 path_len
= strlen(path
);
206 path_last_char
= &path
[path_len
];
212 expanded_path_len
= 0;
214 /* We iterate over the provided path to expand the "//", "../" and "./" */
215 for (curr_char
= path
; curr_char
<= path_last_char
; curr_char
= next_slash
+ 1) {
216 /* Find the next forward slash. */
217 size_t curr_token_len
;
219 if (curr_char
== path_last_char
) {
224 next_slash
= memchr(curr_char
, '/', path_last_char
- curr_char
);
225 if (next_slash
== NULL
) {
226 /* Reached the end of the provided path. */
227 next_slash
= path_last_char
;
230 /* Compute how long is the previous token. */
231 curr_token_len
= next_slash
- curr_char
;
232 switch(curr_token_len
) {
235 * The pointer has not move meaning that curr_char is
236 * pointing to a slash. It that case there is no token
237 * to copy, so continue the iteration to find the next
243 * The pointer moved 1 character. Check if that
244 * character is a dot ('.'), if it is: omit it, else
245 * copy the token to the normalized path.
247 if (curr_char
[0] == '.') {
253 * The pointer moved 2 characters. Check if these
254 * characters are double dots ('..'). If that is the
255 * case, we need to remove the last token of the
258 if (curr_char
[0] == '.' && curr_char
[1] == '.') {
260 * Find the previous path component by
261 * using the memrchr function to find the
262 * previous forward slash and substract that
263 * len to the resulting path.
265 prev_slash
= lttng_memrchr(path
, '/', expanded_path_len
);
267 * If prev_slash is NULL, we reached the
268 * beginning of the path. We can't go back any
271 if (prev_slash
!= NULL
) {
272 expanded_path_len
= prev_slash
- path
;
282 * Copy the current token which is neither a '.' nor a '..'.
284 path
[expanded_path_len
++] = '/';
285 memcpy(&path
[expanded_path_len
], curr_char
, curr_token_len
);
286 expanded_path_len
+= curr_token_len
;
289 if (expanded_path_len
== 0) {
290 path
[expanded_path_len
++] = '/';
293 path
[expanded_path_len
] = '\0';
300 * Make a full resolution of the given path even if it doesn't exist.
301 * This function uses the utils_partial_realpath function to resolve
302 * symlinks and relatives paths at the start of the string, and
303 * implements functionnalities to resolve the './' and '../' strings
304 * in the middle of a path. This function is only necessary because
305 * realpath(3) does not accept to resolve unexistent paths.
306 * The returned string was allocated in the function, it is thus of
307 * the responsibility of the caller to free this memory.
310 char *_utils_expand_path(const char *path
, bool keep_symlink
)
313 char *absolute_path
= NULL
;
315 bool is_dot
, is_dotdot
;
322 /* Allocate memory for the absolute_path */
323 absolute_path
= zmalloc(LTTNG_PATH_MAX
);
324 if (absolute_path
== NULL
) {
325 PERROR("zmalloc expand path");
329 if (path
[0] == '/') {
330 ret
= lttng_strncpy(absolute_path
, path
, LTTNG_PATH_MAX
);
332 ERR("Path exceeds maximal size of %i bytes", LTTNG_PATH_MAX
);
337 * This is a relative path. We need to get the present working
338 * directory and start the path walk from there.
340 char current_working_dir
[LTTNG_PATH_MAX
];
343 cwd_ret
= getcwd(current_working_dir
, sizeof(current_working_dir
));
348 * Get the number of character in the CWD and allocate an array
349 * to can hold it and the path provided by the caller.
351 ret
= snprintf(absolute_path
, LTTNG_PATH_MAX
, "%s/%s",
352 current_working_dir
, path
);
353 if (ret
>= LTTNG_PATH_MAX
) {
354 ERR("Concatenating current working directory %s and path %s exceeds maximal size of %i bytes",
355 current_working_dir
, path
, LTTNG_PATH_MAX
);
361 /* Resolve partially our path */
362 absolute_path
= utils_partial_realpath(absolute_path
,
363 absolute_path
, LTTNG_PATH_MAX
);
366 ret
= expand_double_slashes_dot_and_dotdot(absolute_path
);
371 /* Identify the last token */
372 last_token
= strrchr(absolute_path
, '/');
374 /* Verify that this token is not a relative path */
375 is_dotdot
= (strcmp(last_token
, "/..") == 0);
376 is_dot
= (strcmp(last_token
, "/.") == 0);
378 /* If it is, take action */
379 if (is_dot
|| is_dotdot
) {
380 /* For both, remove this token */
383 /* If it was a reference to parent directory, go back one more time */
385 last_token
= strrchr(absolute_path
, '/');
387 /* If there was only one level left, we keep the first '/' */
388 if (last_token
== absolute_path
) {
396 return absolute_path
;
403 char *utils_expand_path(const char *path
)
405 return _utils_expand_path(path
, true);
409 char *utils_expand_path_keep_symlink(const char *path
)
411 return _utils_expand_path(path
, false);
414 * Create a pipe in dst.
417 int utils_create_pipe(int *dst
)
427 PERROR("create pipe");
434 * Create pipe and set CLOEXEC flag to both fd.
436 * Make sure the pipe opened by this function are closed at some point. Use
437 * utils_close_pipe().
440 int utils_create_pipe_cloexec(int *dst
)
448 ret
= utils_create_pipe(dst
);
453 for (i
= 0; i
< 2; i
++) {
454 ret
= fcntl(dst
[i
], F_SETFD
, FD_CLOEXEC
);
456 PERROR("fcntl pipe cloexec");
466 * Create pipe and set fd flags to FD_CLOEXEC and O_NONBLOCK.
468 * Make sure the pipe opened by this function are closed at some point. Use
469 * utils_close_pipe(). Using pipe() and fcntl rather than pipe2() to
470 * support OSes other than Linux 2.6.23+.
473 int utils_create_pipe_cloexec_nonblock(int *dst
)
481 ret
= utils_create_pipe(dst
);
486 for (i
= 0; i
< 2; i
++) {
487 ret
= fcntl(dst
[i
], F_SETFD
, FD_CLOEXEC
);
489 PERROR("fcntl pipe cloexec");
493 * Note: we override any flag that could have been
494 * previously set on the fd.
496 ret
= fcntl(dst
[i
], F_SETFL
, O_NONBLOCK
);
498 PERROR("fcntl pipe nonblock");
508 * Close both read and write side of the pipe.
511 void utils_close_pipe(int *src
)
519 for (i
= 0; i
< 2; i
++) {
527 PERROR("close pipe");
533 * Create a new string using two strings range.
536 char *utils_strdupdelim(const char *begin
, const char *end
)
540 str
= zmalloc(end
- begin
+ 1);
542 PERROR("zmalloc strdupdelim");
546 memcpy(str
, begin
, end
- begin
);
547 str
[end
- begin
] = '\0';
554 * Set CLOEXEC flag to the give file descriptor.
557 int utils_set_fd_cloexec(int fd
)
566 ret
= fcntl(fd
, F_SETFD
, FD_CLOEXEC
);
568 PERROR("fcntl cloexec");
577 * Create pid file to the given path and filename.
580 int utils_create_pid_file(pid_t pid
, const char *filepath
)
587 fp
= fopen(filepath
, "w");
589 PERROR("open pid file %s", filepath
);
594 ret
= fprintf(fp
, "%d\n", (int) pid
);
596 PERROR("fprintf pid file");
603 DBG("Pid %d written in file %s", (int) pid
, filepath
);
610 * Create lock file to the given path and filename.
611 * Returns the associated file descriptor, -1 on error.
614 int utils_create_lock_file(const char *filepath
)
622 memset(&lock
, 0, sizeof(lock
));
623 fd
= open(filepath
, O_CREAT
| O_WRONLY
, S_IRUSR
| S_IWUSR
|
626 PERROR("open lock file %s", filepath
);
632 * Attempt to lock the file. If this fails, there is
633 * already a process using the same lock file running
634 * and we should exit.
636 lock
.l_whence
= SEEK_SET
;
637 lock
.l_type
= F_WRLCK
;
639 ret
= fcntl(fd
, F_SETLK
, &lock
);
641 PERROR("fcntl lock file");
642 ERR("Could not get lock file %s, another instance is running.",
645 PERROR("close lock file");
656 * On some filesystems (e.g. nfs), mkdir will validate access rights before
657 * checking for the existence of the path element. This means that on a setup
658 * where "/home/" is a mounted NFS share, and running as an unpriviledged user,
659 * recursively creating a path of the form "/home/my_user/trace/" will fail with
660 * EACCES on mkdir("/home", ...).
662 * Performing a stat(...) on the path to check for existence allows us to
663 * work around this behaviour.
666 int mkdir_check_exists(const char *path
, mode_t mode
)
671 ret
= stat(path
, &st
);
673 if (S_ISDIR(st
.st_mode
)) {
674 /* Directory exists, skip. */
677 /* Exists, but is not a directory. */
685 * Let mkdir handle other errors as the caller expects mkdir
688 ret
= mkdir(path
, mode
);
694 * Create directory using the given path and mode.
696 * On success, return 0 else a negative error code.
699 int utils_mkdir(const char *path
, mode_t mode
, int uid
, int gid
)
703 if (uid
< 0 || gid
< 0) {
704 ret
= mkdir_check_exists(path
, mode
);
706 ret
= run_as_mkdir(path
, mode
, uid
, gid
);
709 if (errno
!= EEXIST
) {
710 PERROR("mkdir %s, uid %d, gid %d", path
? path
: "NULL",
721 * Internal version of mkdir_recursive. Runs as the current user.
722 * Don't call directly; use utils_mkdir_recursive().
724 * This function is ominously marked as "unsafe" since it should only
725 * be called by a caller that has transitioned to the uid and gid under which
726 * the directory creation should occur.
729 int _utils_mkdir_recursive_unsafe(const char *path
, mode_t mode
)
731 char *p
, tmp
[PATH_MAX
];
737 ret
= snprintf(tmp
, sizeof(tmp
), "%s", path
);
739 PERROR("snprintf mkdir");
744 if (tmp
[len
- 1] == '/') {
748 for (p
= tmp
+ 1; *p
; p
++) {
751 if (tmp
[strlen(tmp
) - 1] == '.' &&
752 tmp
[strlen(tmp
) - 2] == '.' &&
753 tmp
[strlen(tmp
) - 3] == '/') {
754 ERR("Using '/../' is not permitted in the trace path (%s)",
759 ret
= mkdir_check_exists(tmp
, mode
);
761 if (errno
!= EACCES
) {
762 PERROR("mkdir recursive");
771 ret
= mkdir_check_exists(tmp
, mode
);
773 PERROR("mkdir recursive last element");
782 * Recursively create directory using the given path and mode, under the
783 * provided uid and gid.
785 * On success, return 0 else a negative error code.
788 int utils_mkdir_recursive(const char *path
, mode_t mode
, int uid
, int gid
)
792 if (uid
< 0 || gid
< 0) {
793 /* Run as current user. */
794 ret
= _utils_mkdir_recursive_unsafe(path
, mode
);
796 ret
= run_as_mkdir_recursive(path
, mode
, uid
, gid
);
799 PERROR("mkdir %s, uid %d, gid %d", path
? path
: "NULL",
807 * path is the output parameter. It needs to be PATH_MAX len.
809 * Return 0 on success or else a negative value.
811 static int utils_stream_file_name(char *path
,
812 const char *path_name
, const char *file_name
,
813 uint64_t size
, uint64_t count
,
817 char full_path
[PATH_MAX
];
818 char *path_name_suffix
= NULL
;
821 ret
= snprintf(full_path
, sizeof(full_path
), "%s/%s",
822 path_name
, file_name
);
824 PERROR("snprintf create output file");
828 /* Setup extra string if suffix or/and a count is needed. */
829 if (size
> 0 && suffix
) {
830 ret
= asprintf(&extra
, "_%" PRIu64
"%s", count
, suffix
);
831 } else if (size
> 0) {
832 ret
= asprintf(&extra
, "_%" PRIu64
, count
);
834 ret
= asprintf(&extra
, "%s", suffix
);
837 PERROR("Allocating extra string to name");
842 * If we split the trace in multiple files, we have to add the count at
843 * the end of the tracefile name.
846 ret
= asprintf(&path_name_suffix
, "%s%s", full_path
, extra
);
848 PERROR("Allocating path name with extra string");
849 goto error_free_suffix
;
851 strncpy(path
, path_name_suffix
, PATH_MAX
- 1);
852 path
[PATH_MAX
- 1] = '\0';
854 ret
= lttng_strncpy(path
, full_path
, PATH_MAX
);
856 ERR("Failed to copy stream file name");
857 goto error_free_suffix
;
860 path
[PATH_MAX
- 1] = '\0';
863 free(path_name_suffix
);
871 * Create the stream file on disk.
873 * Return 0 on success or else a negative value.
876 int utils_create_stream_file(const char *path_name
, char *file_name
, uint64_t size
,
877 uint64_t count
, int uid
, int gid
, char *suffix
)
879 int ret
, flags
, mode
;
882 ret
= utils_stream_file_name(path
, path_name
, file_name
,
883 size
, count
, suffix
);
889 * With the session rotation feature on the relay, we might need to seek
890 * and truncate a tracefile, so we need read and write access.
892 flags
= O_RDWR
| O_CREAT
| O_TRUNC
;
893 /* Open with 660 mode */
894 mode
= S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
;
896 if (uid
< 0 || gid
< 0) {
897 ret
= open(path
, flags
, mode
);
899 ret
= run_as_open(path
, flags
, mode
, uid
, gid
);
902 PERROR("open stream path %s", path
);
909 * Unlink the stream tracefile from disk.
911 * Return 0 on success or else a negative value.
914 int utils_unlink_stream_file(const char *path_name
, char *file_name
, uint64_t size
,
915 uint64_t count
, int uid
, int gid
, char *suffix
)
920 ret
= utils_stream_file_name(path
, path_name
, file_name
,
921 size
, count
, suffix
);
925 if (uid
< 0 || gid
< 0) {
928 ret
= run_as_unlink(path
, uid
, gid
);
934 DBG("utils_unlink_stream_file %s returns %d", path
, ret
);
939 * Change the output tracefile according to the given size and count The
940 * new_count pointer is set during this operation.
942 * From the consumer, the stream lock MUST be held before calling this function
943 * because we are modifying the stream status.
945 * Return 0 on success or else a negative value.
948 int utils_rotate_stream_file(char *path_name
, char *file_name
, uint64_t size
,
949 uint64_t count
, int uid
, int gid
, int out_fd
, uint64_t *new_count
,
958 PERROR("Closing tracefile");
965 * In tracefile rotation, for the relay daemon we need
966 * to unlink the old file if present, because it may
967 * still be open in reading by the live thread, and we
968 * need to ensure that we do not overwrite the content
969 * between get_index and get_packet. Since we have no
970 * way to verify integrity of the data content compared
971 * to the associated index, we need to ensure the reader
972 * has exclusive access to the file content, and that
973 * the open of the data file is performed in get_index.
974 * Unlinking the old file rather than overwriting it
978 *new_count
= (*new_count
+ 1) % count
;
980 ret
= utils_unlink_stream_file(path_name
, file_name
, size
,
981 new_count
? *new_count
: 0, uid
, gid
, 0);
982 if (ret
< 0 && errno
!= ENOENT
) {
991 ret
= utils_create_stream_file(path_name
, file_name
, size
,
992 new_count
? *new_count
: 0, uid
, gid
, 0);
1007 * Parse a string that represents a size in human readable format. It
1008 * supports decimal integers suffixed by 'k', 'K', 'M' or 'G'.
1010 * The suffix multiply the integer by:
1015 * @param str The string to parse.
1016 * @param size Pointer to a uint64_t that will be filled with the
1019 * @return 0 on success, -1 on failure.
1022 int utils_parse_size_suffix(const char * const str
, uint64_t * const size
)
1027 const char *str_end
;
1031 DBG("utils_parse_size_suffix: received a NULL string.");
1036 /* strtoull will accept a negative number, but we don't want to. */
1037 if (strchr(str
, '-') != NULL
) {
1038 DBG("utils_parse_size_suffix: invalid size string, should not contain '-'.");
1043 /* str_end will point to the \0 */
1044 str_end
= str
+ strlen(str
);
1046 base_size
= strtoull(str
, &num_end
, 0);
1048 PERROR("utils_parse_size_suffix strtoull");
1053 if (num_end
== str
) {
1054 /* strtoull parsed nothing, not good. */
1055 DBG("utils_parse_size_suffix: strtoull had nothing good to parse.");
1060 /* Check if a prefix is present. */
1078 DBG("utils_parse_size_suffix: invalid suffix.");
1083 /* Check for garbage after the valid input. */
1084 if (num_end
!= str_end
) {
1085 DBG("utils_parse_size_suffix: Garbage after size string.");
1090 *size
= base_size
<< shift
;
1092 /* Check for overflow */
1093 if ((*size
>> shift
) != base_size
) {
1094 DBG("utils_parse_size_suffix: oops, overflow detected.");
1105 * Parse a string that represents a time in human readable format. It
1106 * supports decimal integers suffixed by 's', 'u', 'm', 'us', and 'ms'.
1108 * The suffix multiply the integer by:
1113 * Note that unit-less numbers are assumed to be microseconds.
1115 * @param str The string to parse, assumed to be NULL-terminated.
1116 * @param time_us Pointer to a uint64_t that will be filled with the
1117 * resulting time in microseconds.
1119 * @return 0 on success, -1 on failure.
1122 int utils_parse_time_suffix(char const * const str
, uint64_t * const time_us
)
1126 long multiplier
= 1;
1127 const char *str_end
;
1131 DBG("utils_parse_time_suffix: received a NULL string.");
1136 /* strtoull will accept a negative number, but we don't want to. */
1137 if (strchr(str
, '-') != NULL
) {
1138 DBG("utils_parse_time_suffix: invalid time string, should not contain '-'.");
1143 /* str_end will point to the \0 */
1144 str_end
= str
+ strlen(str
);
1146 base_time
= strtoull(str
, &num_end
, 10);
1148 PERROR("utils_parse_time_suffix strtoull on string \"%s\"", str
);
1153 if (num_end
== str
) {
1154 /* strtoull parsed nothing, not good. */
1155 DBG("utils_parse_time_suffix: strtoull had nothing good to parse.");
1160 /* Check if a prefix is present. */
1164 /* Skip another letter in the 'us' case. */
1165 num_end
+= (*(num_end
+ 1) == 's') ? 2 : 1;
1169 /* Skip another letter in the 'ms' case. */
1170 num_end
+= (*(num_end
+ 1) == 's') ? 2 : 1;
1173 multiplier
= 1000000;
1179 DBG("utils_parse_time_suffix: invalid suffix.");
1184 /* Check for garbage after the valid input. */
1185 if (num_end
!= str_end
) {
1186 DBG("utils_parse_time_suffix: Garbage after time string.");
1191 *time_us
= base_time
* multiplier
;
1193 /* Check for overflow */
1194 if ((*time_us
/ multiplier
) != base_time
) {
1195 DBG("utils_parse_time_suffix: oops, overflow detected.");
1206 * fls: returns the position of the most significant bit.
1207 * Returns 0 if no bit is set, else returns the position of the most
1208 * significant bit (from 1 to 32 on 32-bit, from 1 to 64 on 64-bit).
1210 #if defined(__i386) || defined(__x86_64)
1211 static inline unsigned int fls_u32(uint32_t x
)
1215 asm("bsrl %1,%0\n\t"
1219 : "=r" (r
) : "rm" (x
));
1225 #if defined(__x86_64)
1227 unsigned int fls_u64(uint64_t x
)
1231 asm("bsrq %1,%0\n\t"
1235 : "=r" (r
) : "rm" (x
));
1242 static __attribute__((unused
))
1243 unsigned int fls_u64(uint64_t x
)
1245 unsigned int r
= 64;
1250 if (!(x
& 0xFFFFFFFF00000000ULL
)) {
1254 if (!(x
& 0xFFFF000000000000ULL
)) {
1258 if (!(x
& 0xFF00000000000000ULL
)) {
1262 if (!(x
& 0xF000000000000000ULL
)) {
1266 if (!(x
& 0xC000000000000000ULL
)) {
1270 if (!(x
& 0x8000000000000000ULL
)) {
1279 static __attribute__((unused
)) unsigned int fls_u32(uint32_t x
)
1281 unsigned int r
= 32;
1286 if (!(x
& 0xFFFF0000U
)) {
1290 if (!(x
& 0xFF000000U
)) {
1294 if (!(x
& 0xF0000000U
)) {
1298 if (!(x
& 0xC0000000U
)) {
1302 if (!(x
& 0x80000000U
)) {
1311 * Return the minimum order for which x <= (1UL << order).
1312 * Return -1 if x is 0.
1315 int utils_get_count_order_u32(uint32_t x
)
1321 return fls_u32(x
- 1);
1325 * Return the minimum order for which x <= (1UL << order).
1326 * Return -1 if x is 0.
1329 int utils_get_count_order_u64(uint64_t x
)
1335 return fls_u64(x
- 1);
1339 * Obtain the value of LTTNG_HOME environment variable, if exists.
1340 * Otherwise returns the value of HOME.
1343 char *utils_get_home_dir(void)
1348 val
= lttng_secure_getenv(DEFAULT_LTTNG_HOME_ENV_VAR
);
1352 val
= lttng_secure_getenv(DEFAULT_LTTNG_FALLBACK_HOME_ENV_VAR
);
1357 /* Fallback on the password file entry. */
1358 pwd
= getpwuid(getuid());
1364 DBG3("Home directory is '%s'", val
);
1371 * Get user's home directory. Dynamically allocated, must be freed
1375 char *utils_get_user_home_dir(uid_t uid
)
1378 struct passwd
*result
;
1379 char *home_dir
= NULL
;
1384 buflen
= sysconf(_SC_GETPW_R_SIZE_MAX
);
1389 buf
= zmalloc(buflen
);
1394 ret
= getpwuid_r(uid
, &pwd
, buf
, buflen
, &result
);
1395 if (ret
|| !result
) {
1396 if (ret
== ERANGE
) {
1404 home_dir
= strdup(pwd
.pw_dir
);
1411 * With the given format, fill dst with the time of len maximum siz.
1413 * Return amount of bytes set in the buffer or else 0 on error.
1416 size_t utils_get_current_time_str(const char *format
, char *dst
, size_t len
)
1420 struct tm
*timeinfo
;
1425 /* Get date and time for session path */
1427 timeinfo
= localtime(&rawtime
);
1428 ret
= strftime(dst
, len
, format
, timeinfo
);
1430 ERR("Unable to strftime with format %s at dst %p of len %zu", format
,
1438 * Return the group ID matching name, else 0 if it cannot be found.
1441 gid_t
utils_get_group_id(const char *name
)
1445 grp
= getgrnam(name
);
1447 static volatile int warn_once
;
1450 WARN("No tracing group detected");
1459 * Return a newly allocated option string. This string is to be used as the
1460 * optstring argument of getopt_long(), see GETOPT(3). opt_count is the number
1461 * of elements in the long_options array. Returns NULL if the string's
1465 char *utils_generate_optstring(const struct option
*long_options
,
1469 size_t string_len
= opt_count
, str_pos
= 0;
1473 * Compute the necessary string length. One letter per option, two when an
1474 * argument is necessary, and a trailing NULL.
1476 for (i
= 0; i
< opt_count
; i
++) {
1477 string_len
+= long_options
[i
].has_arg
? 1 : 0;
1480 optstring
= zmalloc(string_len
);
1485 for (i
= 0; i
< opt_count
; i
++) {
1486 if (!long_options
[i
].name
) {
1487 /* Got to the trailing NULL element */
1491 if (long_options
[i
].val
!= '\0') {
1492 optstring
[str_pos
++] = (char) long_options
[i
].val
;
1493 if (long_options
[i
].has_arg
) {
1494 optstring
[str_pos
++] = ':';
1504 * Try to remove a hierarchy of empty directories, recursively. Don't unlink
1505 * any file. Try to rmdir any empty directory within the hierarchy.
1508 int utils_recursive_rmdir(const char *path
)
1512 int dir_fd
, ret
= 0, closeret
, is_empty
= 1;
1513 struct dirent
*entry
;
1515 /* Open directory */
1516 dir
= opendir(path
);
1518 PERROR("Cannot open '%s' path", path
);
1521 dir_fd
= lttng_dirfd(dir
);
1523 PERROR("lttng_dirfd");
1527 path_len
= strlen(path
);
1528 while ((entry
= readdir(dir
))) {
1531 char filename
[PATH_MAX
];
1533 if (!strcmp(entry
->d_name
, ".")
1534 || !strcmp(entry
->d_name
, "..")) {
1538 name_len
= strlen(entry
->d_name
);
1539 if (path_len
+ name_len
+ 2 > sizeof(filename
)) {
1540 ERR("Failed to remove file: path name too long (%s/%s)",
1541 path
, entry
->d_name
);
1544 if (snprintf(filename
, sizeof(filename
), "%s/%s",
1545 path
, entry
->d_name
) < 0) {
1546 ERR("Failed to format path.");
1550 if (stat(filename
, &st
)) {
1555 if (S_ISDIR(st
.st_mode
)) {
1556 char subpath
[PATH_MAX
];
1558 strncpy(subpath
, path
, PATH_MAX
);
1559 subpath
[PATH_MAX
- 1] = '\0';
1560 strncat(subpath
, "/",
1561 PATH_MAX
- strlen(subpath
) - 1);
1562 strncat(subpath
, entry
->d_name
,
1563 PATH_MAX
- strlen(subpath
) - 1);
1564 if (utils_recursive_rmdir(subpath
)) {
1567 } else if (S_ISREG(st
.st_mode
)) {
1575 closeret
= closedir(dir
);
1580 DBG3("Attempting rmdir %s", path
);
1587 int utils_truncate_stream_file(int fd
, off_t length
)
1592 ret
= ftruncate(fd
, length
);
1594 PERROR("ftruncate");
1597 lseek_ret
= lseek(fd
, length
, SEEK_SET
);
1598 if (lseek_ret
< 0) {
1607 static const char *get_man_bin_path(void)
1609 char *env_man_path
= lttng_secure_getenv(DEFAULT_MAN_BIN_PATH_ENV
);
1612 return env_man_path
;
1615 return DEFAULT_MAN_BIN_PATH
;
1619 int utils_show_help(int section
, const char *page_name
,
1620 const char *help_msg
)
1622 char section_string
[8];
1623 const char *man_bin_path
= get_man_bin_path();
1627 printf("%s", help_msg
);
1631 /* Section integer -> section string */
1632 ret
= sprintf(section_string
, "%d", section
);
1633 assert(ret
> 0 && ret
< 8);
1636 * Execute man pager.
1638 * We provide -M to man here because LTTng-tools can
1639 * be installed outside /usr, in which case its man pages are
1640 * not located in the default /usr/share/man directory.
1642 ret
= execlp(man_bin_path
, "man", "-M", MANPATH
,
1643 section_string
, page_name
, NULL
);