2 * Copyright (C) 2004-2013 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file string.c Memory allocation and string handling functions. */
9 #include <sys/time.h> /* gettimeofday */
11 #include <sys/utsname.h> /* uname() */
20 * Paraslash's version of realloc().
22 * \param p Pointer to the memory block, may be \p NULL.
23 * \param size The desired new size.
25 * A wrapper for realloc(3). It calls \p exit(\p EXIT_FAILURE) on errors,
26 * i.e. there is no need to check the return value in the caller.
28 * \return A pointer to the newly allocated memory, which is suitably aligned
29 * for any kind of variable and may be different from \a p.
33 __must_check __malloc void *para_realloc(void *p, size_t size)
36 * No need to check for NULL pointers: If p is NULL, the call
37 * to realloc is equivalent to malloc(size)
40 if (!(p = realloc(p, size))) {
41 PARA_EMERG_LOG("realloc failed (size = %zu), aborting\n",
49 * Paraslash's version of malloc().
51 * \param size The desired new size.
53 * A wrapper for malloc(3) which exits on errors.
55 * \return A pointer to the allocated memory, which is suitably aligned for any
60 __must_check __malloc void *para_malloc(size_t size)
67 PARA_EMERG_LOG("malloc failed (size = %zu), aborting\n",
75 * Paraslash's version of calloc().
77 * \param size The desired new size.
79 * A wrapper for calloc(3) which exits on errors.
81 * \return A pointer to the allocated and zeroed-out memory, which is suitably
82 * aligned for any kind of variable.
86 __must_check __malloc void *para_calloc(size_t size)
88 void *ret = para_malloc(size);
95 * Paraslash's version of strdup().
97 * \param s The string to be duplicated.
99 * A wrapper for strdup(3). It calls \p exit(EXIT_FAILURE) on errors, i.e.
100 * there is no need to check the return value in the caller.
102 * \return A pointer to the duplicated string. If \a s was the \p NULL pointer,
103 * an pointer to an empty string is returned.
107 __must_check __malloc char *para_strdup(const char *s)
111 if ((ret = strdup(s? s: "")))
113 PARA_EMERG_LOG("strdup failed, aborting\n");
118 * Print a formated message to a dynamically allocated string.
120 * \param result The formated string is returned here.
121 * \param fmt The format string.
122 * \param ap Initialized list of arguments.
124 * This function is similar to vasprintf(), a GNU extension which is not in C
125 * or POSIX. It allocates a string large enough to hold the output including
126 * the terminating null byte. The allocated string is returned via the first
127 * argument and must be freed by the caller. However, unlike vasprintf(), this
128 * function calls exit() if insufficient memory is available, while vasprintf()
129 * returns -1 in this case.
131 * \return Number of bytes written, not including the terminating \p NULL
134 * \sa printf(3), vsnprintf(3), va_start(3), vasprintf(3), \ref xasprintf().
136 __printf_2_0 unsigned xvasprintf(char **result, const char *fmt, va_list ap)
142 *result = para_malloc(size + 1);
144 ret = vsnprintf(*result, size, fmt, aq);
147 if (ret < size) /* OK */
150 *result = para_realloc(*result, size);
152 ret = vsnprintf(*result, size, fmt, aq);
154 assert(ret >= 0 && ret < size);
159 * Print to a dynamically allocated string, variable number of arguments.
161 * \param result See \ref xvasprintf().
162 * \param fmt Usual format string.
164 * \return The return value of the underlying call to \ref xvasprintf().
166 * \sa \ref xvasprintf() and the references mentioned there.
168 __printf_2_3 unsigned xasprintf(char **result, const char *fmt, ...)
174 ret = xvasprintf(result, fmt, ap);
180 * Allocate a sufficiently large string and print into it.
182 * \param fmt A usual format string.
184 * Produce output according to \p fmt. No artificial bound on the length of the
185 * resulting string is imposed.
187 * \return This function either returns a pointer to a string that must be
188 * freed by the caller or aborts without returning.
190 * \sa printf(3), xasprintf().
192 __must_check __printf_1_2 __malloc char *make_message(const char *fmt, ...)
198 xvasprintf(&msg, fmt, ap);
204 * Free the content of a pointer and set it to \p NULL.
206 * This is equivalent to "free(*arg); *arg = NULL;".
208 * \param arg The pointer whose content should be freed.
210 void freep(void *arg)
212 void **ptr = (void **)arg;
218 * Paraslash's version of strcat().
220 * \param a String to be appended to.
221 * \param b String to append.
223 * Append \p b to \p a.
225 * \return If \a a is \p NULL, return a pointer to a copy of \a b, i.e.
226 * para_strcat(NULL, b) is equivalent to para_strdup(b). If \a b is \p NULL,
227 * return \a a without making a copy of \a a. Otherwise, construct the
228 * concatenation \a c, free \a a (but not \a b) and return \a c.
232 __must_check __malloc char *para_strcat(char *a, const char *b)
237 return para_strdup(b);
240 tmp = make_message("%s%s", a, b);
246 * Paraslash's version of dirname().
248 * \param name Pointer to the full path.
250 * Compute the directory component of \p name.
252 * \return If \a name is \p NULL or the empty string, return \p NULL.
253 * Otherwise, Make a copy of \a name and return its directory component. Caller
254 * is responsible to free the result.
256 __must_check __malloc char *para_dirname(const char *name)
262 ret = para_strdup(name);
263 p = strrchr(ret, '/');
272 * Paraslash's version of basename().
274 * \param name Pointer to the full path.
276 * Compute the filename component of \a name.
278 * \return \p NULL if (a) \a name is the empty string or \p NULL, or (b) name
279 * ends with a slash. Otherwise, a pointer within \a name is returned. Caller
280 * must not free the result.
282 __must_check char *para_basename(const char *name)
288 ret = strrchr(name, '/');
296 * Cut trailing newline.
298 * \param buf The string to be chopped.
300 * Replace the last character in \p buf by zero if it is equal to
301 * the newline character.
309 if (buf[n - 1] == '\n')
314 * Get the logname of the current user.
316 * \return A dynamically allocated string that must be freed by the caller. On
317 * errors, the string "unknown_user" is returned, i.e. this function never
322 __must_check __malloc char *para_logname(void)
324 struct passwd *pw = getpwuid(getuid());
325 return para_strdup(pw? pw->pw_name : "unknown_user");
329 * Get the home directory of the current user.
331 * \return A dynamically allocated string that must be freed by the caller. If
332 * the home directory could not be found, this function returns "/tmp".
334 __must_check __malloc char *para_homedir(void)
336 struct passwd *pw = getpwuid(getuid());
337 return para_strdup(pw? pw->pw_dir : "/tmp");
341 * Get the own hostname.
343 * \return A dynamically allocated string containing the hostname.
347 __malloc char *para_hostname(void)
352 return para_strdup(u.nodename);
356 * Call a custom function for each complete line.
358 * \param flags Any combination of flags defined in \ref for_each_line_flags.
359 * \param buf The buffer containing data separated by newlines.
360 * \param size The number of bytes in \a buf.
361 * \param line_handler The custom function.
362 * \param private_data Pointer passed to \a line_handler.
364 * For each complete line in \p buf, \p line_handler is called. The first
365 * argument to \p line_handler is (a copy of) the current line, and \p
366 * private_data is passed as the second argument. If the \p FELF_READ_ONLY
367 * flag is unset, a pointer into \a buf is passed to the line handler,
368 * otherwise a pointer to a copy of the current line is passed instead. This
369 * copy is freed immediately after the line handler returns.
371 * The function returns if \p line_handler returns a negative value or no more
372 * lines are in the buffer. The rest of the buffer (last chunk containing an
373 * incomplete line) is moved to the beginning of the buffer if FELF_READ_ONLY is
376 * \return On success this function returns the number of bytes not handled to
377 * \p line_handler. The only possible error is a negative return value from the
378 * line handler. In this case processing stops and the return value of the line
379 * handler is returned to indicate failure.
381 * \sa \ref for_each_line_flags.
383 int for_each_line(unsigned flags, char *buf, size_t size,
384 line_handler_t *line_handler, void *private_data)
386 char *start = buf, *end;
387 int ret, i, num_lines = 0;
389 // PARA_NOTICE_LOG("buf: %s\n", buf);
390 while (start < buf + size) {
394 next_cr = memchr(start, '\n', buf + size - start);
395 next_null = memchr(start, '\0', buf + size - start);
396 if (!next_cr && !next_null)
398 if (next_cr && next_null) {
399 end = next_cr < next_null? next_cr : next_null;
400 } else if (next_null) {
405 if (!(flags & FELF_DISCARD_FIRST) || start != buf) {
406 if (flags & FELF_READ_ONLY) {
407 size_t s = end - start;
408 char *b = para_malloc(s + 1);
411 ret = line_handler(b, private_data);
415 ret = line_handler(start, private_data);
422 i = buf + size - start;
423 if (i && i != size && !(flags & FELF_READ_ONLY))
424 memmove(buf, start, i);
428 /** Return the hex characters of the lower 4 bits. */
429 #define hex(a) (hexchar[(a) & 15])
431 static void write_size_header(char *buf, int n)
433 static char hexchar[] = "0123456789abcdef";
435 buf[0] = hex(n >> 12);
436 buf[1] = hex(n >> 8);
437 buf[2] = hex(n >> 4);
443 * Read a four-byte hex-number and return its value.
445 * Each status item sent by para_server is prefixed with such a hex number in
446 * ASCII which describes the size of the status item.
448 * \param buf The buffer which must be at least four bytes long.
450 * \return The value of the hex number on success, \p -E_SIZE_PREFIX if the
451 * buffer did not contain only hex digits.
453 int read_size_header(const char *buf)
457 for (i = 0; i < 4; i++) {
458 unsigned char c = buf[i];
460 if (c >= '0' && c <= '9') {
464 if (c >= 'a' && c <= 'f') {
468 return -E_SIZE_PREFIX;
471 return -E_SIZE_PREFIX;
476 * Safely print into a buffer at a given offset.
478 * \param b Determines the buffer, its size, and the offset.
479 * \param fmt The format string.
481 * This function prints into the buffer given by \a b at the offset which is
482 * also given by \a b. If there is not enough space to hold the result, the
483 * buffer size is doubled until the underlying call to vsnprintf() succeeds
484 * or the size of the buffer exceeds the maximal size specified in \a b.
486 * In the latter case the unmodified \a buf and \a offset values as well as the
487 * private_data pointer of \a b are passed to the \a max_size_handler of \a b.
488 * If this function succeeds, i.e. returns a non-negative value, the offset of
489 * \a b is reset to zero and the given data is written to the beginning of the
490 * buffer. If \a max_size_handler() returns a negative value, this value is
491 * returned by \a para_printf().
493 * Upon return, the offset of \a b is adjusted accordingly so that subsequent
494 * calls to this function append data to what is already contained in the
497 * It's OK to call this function with \p b->buf being \p NULL. In this case, an
498 * initial buffer is allocated.
500 * \return The number of bytes printed into the buffer (not including the
501 * terminating \p NULL byte) on success, negative on errors. If there is no
502 * size-bound on \a b, i.e. if \p b->max_size is zero, this function never
505 * \sa make_message(), vsnprintf(3).
507 __printf_2_3 int para_printf(struct para_buffer *b, const char *fmt, ...)
509 int ret, sz_off = (b->flags & PBF_SIZE_PREFIX)? 5 : 0;
512 b->buf = para_malloc(128);
517 char *p = b->buf + b->offset;
518 size_t size = b->size - b->offset;
523 ret = vsnprintf(p + sz_off, size - sz_off, fmt, ap);
525 if (ret > -1 && ret < size - sz_off) { /* success */
526 b->offset += ret + sz_off;
528 write_size_header(p, ret);
532 /* check if we may grow the buffer */
533 if (!b->max_size || 2 * b->size < b->max_size) { /* yes */
534 /* try again with more space */
536 b->buf = para_realloc(b->buf, b->size);
539 /* can't grow buffer */
540 if (!b->offset || !b->max_size_handler) /* message too large */
541 return -ERRNO_TO_PARA_ERROR(ENOSPC);
542 ret = b->max_size_handler(b->buf, b->offset, b->private_data);
549 /** \cond llong_minmax */
550 /* LLONG_MAX and LLONG_MIN might not be defined. */
552 #define LLONG_MAX 9223372036854775807LL
555 #define LLONG_MIN (-LLONG_MAX - 1LL)
557 /** \endcond llong_minmax */
560 * Convert a string to a 64-bit signed integer value.
562 * \param str The string to be converted.
563 * \param value Result pointer.
567 * \sa para_atoi32(), strtol(3), atoi(3).
569 int para_atoi64(const char *str, int64_t *value)
574 errno = 0; /* To distinguish success/failure after call */
575 tmp = strtoll(str, &endptr, 10);
576 if (errno == ERANGE && (tmp == LLONG_MAX || tmp == LLONG_MIN))
577 return -E_ATOI_OVERFLOW;
578 if (errno != 0 && tmp == 0) /* other error */
581 return -E_ATOI_NO_DIGITS;
582 if (*endptr != '\0') /* Further characters after number */
583 return -E_ATOI_JUNK_AT_END;
589 * Convert a string to a 32-bit signed integer value.
591 * \param str The string to be converted.
592 * \param value Result pointer.
598 int para_atoi32(const char *str, int32_t *value)
602 const int32_t max = 2147483647;
604 ret = para_atoi64(str, &tmp);
607 if (tmp > max || tmp < -max - 1)
608 return -E_ATOI_OVERFLOW;
613 static inline int loglevel_equal(const char *arg, const char * const ll)
615 return !strncasecmp(arg, ll, strlen(ll));
619 * Compute the loglevel number from its name.
621 * \param txt The name of the loglevel (debug, info, ...).
623 * \return The numeric representation of the loglevel name.
625 int get_loglevel_by_name(const char *txt)
627 if (loglevel_equal(txt, "debug"))
629 if (loglevel_equal(txt, "info"))
631 if (loglevel_equal(txt, "notice"))
633 if (loglevel_equal(txt, "warning"))
635 if (loglevel_equal(txt, "error"))
637 if (loglevel_equal(txt, "crit"))
639 if (loglevel_equal(txt, "emerg"))
644 static int get_next_word(const char *buf, const char *delim, char **word)
646 enum line_state_flags {LSF_HAVE_WORD = 1, LSF_BACKSLASH = 2,
647 LSF_SINGLE_QUOTE = 4, LSF_DOUBLE_QUOTE = 8};
652 out = para_malloc(strlen(buf) + 1);
655 for (in = buf; *in; in++) {
660 if (state & LSF_BACKSLASH) /* \\ */
662 state |= LSF_BACKSLASH;
663 state |= LSF_HAVE_WORD;
667 if (state & LSF_BACKSLASH) { /* \n or \t */
668 *out++ = (*in == 'n')? '\n' : '\t';
669 state &= ~LSF_BACKSLASH;
674 if (state & LSF_BACKSLASH) /* \" */
676 if (state & LSF_SINGLE_QUOTE) /* '" */
678 if (state & LSF_DOUBLE_QUOTE) {
679 state &= ~LSF_DOUBLE_QUOTE;
682 state |= LSF_HAVE_WORD;
683 state |= LSF_DOUBLE_QUOTE;
686 if (state & LSF_BACKSLASH) /* \' */
688 if (state & LSF_DOUBLE_QUOTE) /* "' */
690 if (state & LSF_SINGLE_QUOTE) {
691 state &= ~LSF_SINGLE_QUOTE;
694 state |= LSF_HAVE_WORD;
695 state |= LSF_SINGLE_QUOTE;
698 for (p = delim; *p; p++) {
701 if (state & LSF_BACKSLASH)
703 if (state & LSF_SINGLE_QUOTE)
705 if (state & LSF_DOUBLE_QUOTE)
707 if (state & LSF_HAVE_WORD)
711 if (*p) /* ignore delimiter at the beginning */
714 state |= LSF_HAVE_WORD;
716 state &= ~LSF_BACKSLASH;
719 if (!(state & LSF_HAVE_WORD))
721 ret = -ERRNO_TO_PARA_ERROR(EINVAL);
722 if (state & LSF_BACKSLASH) {
723 PARA_ERROR_LOG("trailing backslash\n");
726 if ((state & LSF_SINGLE_QUOTE) || (state & LSF_DOUBLE_QUOTE)) {
727 PARA_ERROR_LOG("unmatched quote character\n");
740 * Get the number of the word the cursor is on.
742 * \param buf The zero-terminated line buffer.
743 * \param delim Characters that separate words.
744 * \param point The cursor position.
746 * \return Zero-based word number.
748 int compute_word_num(const char *buf, const char *delim, int point)
754 for (p = buf, num_words = 0; ; p += ret, num_words++) {
755 ret = get_next_word(p, delim, &word);
759 if (p + ret >= buf + point)
766 * Free an array of words created by create_argv() or create_shifted_argv().
768 * \param argv A pointer previously obtained by \ref create_argv().
770 void free_argv(char **argv)
776 for (i = 0; argv[i]; i++)
781 static int create_argv_offset(int offset, const char *buf, const char *delim,
784 char *word, **argv = para_malloc((offset + 1) * sizeof(char *));
788 for (i = 0; i < offset; i++)
790 for (p = buf; p && *p; p += ret, i++) {
791 ret = get_next_word(p, delim, &word);
796 argv = para_realloc(argv, (i + 2) * sizeof(char*));
811 * Split a buffer into words.
813 * This parser honors single and double quotes, backslash-escaped characters
814 * and special characters like \p \\n. The result contains pointers to copies
815 * of the words contained in \a buf and has to be freed by using \ref
818 * \param buf The buffer to be split.
819 * \param delim Each character in this string is treated as a separator.
820 * \param result The array of words is returned here.
822 * \return Number of words in \a buf, negative on errors.
824 int create_argv(const char *buf, const char *delim, char ***result)
826 return create_argv_offset(0, buf, delim, result);
830 * Split a buffer into words, offset one.
832 * This is similar to \ref create_argv() but the returned array is one element
833 * larger, words start at index one and element zero is initialized to \p NULL.
834 * Callers must set element zero to a non-NULL value before calling free_argv()
835 * on the returned array to avoid a memory leak.
837 * \param buf See \ref create_argv().
838 * \param delim See \ref create_argv().
839 * \param result See \ref create_argv().
841 * \return Number of words plus one on success, negative on errors.
843 int create_shifted_argv(const char *buf, const char *delim, char ***result)
845 return create_argv_offset(1, buf, delim, result);
849 * Find out if the given string is contained in the arg vector.
851 * \param arg The string to look for.
852 * \param argv The array to search.
854 * \return The first index whose value equals \a arg, or \p -E_ARG_NOT_FOUND if
855 * arg was not found in \a argv.
857 int find_arg(const char *arg, char **argv)
862 return -E_ARG_NOT_FOUND;
863 for (i = 0; argv[i]; i++)
864 if (strcmp(arg, argv[i]) == 0)
866 return -E_ARG_NOT_FOUND;
870 * Compile a regular expression.
872 * This simple wrapper calls regcomp() and logs a message on errors.
874 * \param preg See regcomp(3).
875 * \param regex See regcomp(3).
876 * \param cflags See regcomp(3).
880 int para_regcomp(regex_t *preg, const char *regex, int cflags)
884 int ret = regcomp(preg, regex, cflags);
888 size = regerror(ret, preg, NULL, 0);
889 buf = para_malloc(size);
890 regerror(ret, preg, buf, size);
891 PARA_ERROR_LOG("%s\n", buf);
897 * strdup() for not necessarily zero-terminated strings.
899 * \param src The source buffer.
900 * \param len The number of bytes to be copied.
902 * \return A 0-terminated buffer of length \a len + 1.
904 * This is similar to strndup(), which is a GNU extension. However, one
905 * difference is that strndup() returns \p NULL if insufficient memory was
906 * available while this function aborts in this case.
908 * \sa strdup(), \ref para_strdup().
910 char *safe_strdup(const char *src, size_t len)
914 assert(len < (size_t)-1);
915 p = para_malloc(len + 1);
923 * Copy the value of a key=value pair.
925 * This checks whether the given buffer starts with "key=", ignoring case. If
926 * yes, a copy of the value is returned. The source buffer may not be
929 * \param src The source buffer.
930 * \param len The number of bytes of the tag.
931 * \param key Only copy if it is the value of this key.
933 * \return A zero-terminated buffer, or \p NULL if the key was
934 * not of the given type.
936 char *key_value_copy(const char *src, size_t len, const char *key)
938 int keylen = strlen(key);
942 if (strncasecmp(src, key, keylen))
944 if (src[keylen] != '=')
946 return safe_strdup(src + keylen + 1, len - keylen - 1);