/*
* Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
+ * Copyright (C) 2013 - Raphaël Beamonte <raphael.beamonte@gmail.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
*/
#define _GNU_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 <regex.h>
+#include <grp.h>
#include <common/common.h>
+#include <common/runas.h>
#include "utils.h"
+#include "defaults.h"
/*
- * 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.
*/
-__attribute__((visibility("hidden")))
-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, *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");
- goto error;
+ /* 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 = strndup(path, next - path);
+
+ /* 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);
+ };
+
+ /* 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;
+ }
}
- 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);
- break;
- default:
- PERROR("realpath utils expand path");
- break;
+ /*
+ * 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);
+
+ /* 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);
+ /*
+ * 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);
+ 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;
+
+ /* Safety net */
+ if (path == NULL) {
goto error;
}
- /* Add end part to expanded path */
- strncat(expanded_path, end_path, PATH_MAX - strlen(expanded_path) - 1);
+ /* Allocate memory for the absolute_path */
+ absolute_path = zmalloc(PATH_MAX);
+ if (absolute_path == NULL) {
+ PERROR("zmalloc expand path");
+ goto error;
+ }
- free(cut_path);
- return expanded_path;
+ /*
+ * 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 = strndup(absolute_path, next - absolute_path);
+
+ /* 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 = strndup(absolute_path, previous - absolute_path);
+
+ /* 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);
+ }
+
+ return absolute_path;
error:
- free(expanded_path);
- free(cut_path);
+ free(absolute_path);
return NULL;
}
/*
* Create a pipe in dst.
*/
-__attribute__((visibility("hidden")))
+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().
*/
-__attribute__((visibility("hidden")))
+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.
*/
-__attribute__((visibility("hidden")))
+LTTNG_HIDDEN
void utils_close_pipe(int *src)
{
int i, ret;
/*
* Create a new string using two strings range.
*/
-__attribute__((visibility("hidden")))
+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", pid);
+ if (ret < 0) {
+ PERROR("fprintf pid file");
+ }
+
+ fclose(fp);
+ DBG("Pid %d written in file %s", pid, filepath);
+error:
+ return ret;
+}
+
+/*
+ * Recursively create directory using the given path and mode.
+ *
+ * On success, return 0 else a negative error code.
+ */
+LTTNG_HIDDEN
+int utils_mkdir_recursive(const char *path, mode_t mode)
+{
+ 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 piece");
+ ret = -errno;
+ } else {
+ ret = 0;
+ }
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * Create the stream tracefile 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, out_fd, flags, mode;
+ char full_path[PATH_MAX], *path_name_suffix = NULL, *path;
+ char *extra = NULL;
+
+ assert(path_name);
+ assert(file_name);
+
+ 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;
+ }
+ path = path_name_suffix;
+ } else {
+ path = full_path;
+ }
+
+ 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) {
+ out_fd = open(path, flags, mode);
+ } else {
+ out_fd = run_as_open(path, flags, mode, uid, gid);
+ }
+ if (out_fd < 0) {
+ PERROR("open stream path %s", path);
+ goto error_open;
+ }
+ ret = out_fd;
+
+error_open:
+ free(path_name_suffix);
+error_free_suffix:
+ free(extra);
+error:
+ 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) {
+ *new_count = (*new_count + 1) % count;
+ } 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;
+}
+
+/**
+ * Prints the error message corresponding to a regex error code.
+ *
+ * @param errcode The error code.
+ * @param regex The regex object that produced the error code.
+ */
+static void regex_print_error(int errcode, regex_t *regex)
+{
+ /* Get length of error message and allocate accordingly */
+ size_t length;
+ char *buffer;
+
+ assert(regex != NULL);
+
+ length = regerror(errcode, regex, NULL, 0);
+ if (length == 0) {
+ ERR("regerror returned a length of 0");
+ return;
+ }
+
+ buffer = zmalloc(length);
+ if (!buffer) {
+ ERR("regex_print_error: zmalloc failed");
+ return;
+ }
+
+ /* Get and print error message */
+ regerror(errcode, regex, buffer, length);
+ ERR("regex error: %s\n", buffer);
+ free(buffer);
+
+}
+
+/**
+ * Parse a string that represents a size in human readable format. It
+ * supports decimal integers suffixed by '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 size_t that will be filled with the
+ * resulting size.
+ *
+ * @return 0 on success, -1 on failure.
+ */
+LTTNG_HIDDEN
+int utils_parse_size_suffix(char *str, uint64_t *size)
+{
+ regex_t regex;
+ int ret;
+ const int nmatch = 3;
+ regmatch_t suffix_match, matches[nmatch];
+ unsigned long long base_size;
+ long shift = 0;
+
+ if (!str) {
+ return 0;
+ }
+
+ /* Compile regex */
+ ret = regcomp(®ex, "^\\(0x\\)\\{0,1\\}[0-9][0-9]*\\([kKMG]\\{0,1\\}\\)$", 0);
+ if (ret != 0) {
+ regex_print_error(ret, ®ex);
+ ret = -1;
+ goto end;
+ }
+
+ /* Match regex */
+ ret = regexec(®ex, str, nmatch, matches, 0);
+ if (ret != 0) {
+ ret = -1;
+ goto free;
+ }
+
+ /* There is a match ! */
+ errno = 0;
+ base_size = strtoull(str, NULL, 0);
+ if (errno != 0) {
+ PERROR("strtoull");
+ ret = -1;
+ goto free;
+ }
+
+ /* Check if there is a suffix */
+ suffix_match = matches[2];
+ if (suffix_match.rm_eo - suffix_match.rm_so == 1) {
+ switch (*(str + suffix_match.rm_so)) {
+ case 'K':
+ case 'k':
+ shift = KIBI_LOG2;
+ break;
+ case 'M':
+ shift = MEBI_LOG2;
+ break;
+ case 'G':
+ shift = GIBI_LOG2;
+ break;
+ default:
+ ERR("parse_human_size: invalid suffix");
+ ret = -1;
+ goto free;
+ }
+ }
+
+ *size = base_size << shift;
+
+ /* Check for overflow */
+ if ((*size >> shift) != base_size) {
+ ERR("parse_size_suffix: oops, overflow detected.");
+ ret = -1;
+ goto free;
+ }
+
+ ret = 0;
+
+free:
+ regfree(®ex);
+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;
+ val = getenv(DEFAULT_LTTNG_HOME_ENV_VAR);
+ if (val != NULL) {
+ return val;
+ }
+ return getenv(DEFAULT_LTTNG_FALLBACK_HOME_ENV_VAR);
+}
+
+/*
+ * 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 %lu", 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;
+}
projects / lttng-tools.git / blobdiff