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)
143 ret = vsnprintf(NULL, 0, fmt, aq);
147 *result = para_malloc(size);
149 ret = vsnprintf(*result, size, fmt, aq);
151 assert(ret >= 0 && ret < size);
156 * Print to a dynamically allocated string, variable number of arguments.
158 * \param result See \ref xvasprintf().
159 * \param fmt Usual format string.
161 * \return The return value of the underlying call to \ref xvasprintf().
163 * \sa \ref xvasprintf() and the references mentioned there.
165 __printf_2_3 unsigned xasprintf(char **result, const char *fmt, ...)
171 ret = xvasprintf(result, fmt, ap);
177 * Allocate a sufficiently large string and print into it.
179 * \param fmt A usual format string.
181 * Produce output according to \p fmt. No artificial bound on the length of the
182 * resulting string is imposed.
184 * \return This function either returns a pointer to a string that must be
185 * freed by the caller or aborts without returning.
187 * \sa printf(3), xasprintf().
189 __must_check __printf_1_2 __malloc char *make_message(const char *fmt, ...)
195 xvasprintf(&msg, fmt, ap);
201 * Free the content of a pointer and set it to \p NULL.
203 * This is equivalent to "free(*arg); *arg = NULL;".
205 * \param arg The pointer whose content should be freed.
207 void freep(void *arg)
209 void **ptr = (void **)arg;
215 * Paraslash's version of strcat().
217 * \param a String to be appended to.
218 * \param b String to append.
220 * Append \p b to \p a.
222 * \return If \a a is \p NULL, return a pointer to a copy of \a b, i.e.
223 * para_strcat(NULL, b) is equivalent to para_strdup(b). If \a b is \p NULL,
224 * return \a a without making a copy of \a a. Otherwise, construct the
225 * concatenation \a c, free \a a (but not \a b) and return \a c.
229 __must_check __malloc char *para_strcat(char *a, const char *b)
234 return para_strdup(b);
237 tmp = make_message("%s%s", a, b);
243 * Paraslash's version of dirname().
245 * \param name Pointer to the full path.
247 * Compute the directory component of \p name.
249 * \return If \a name is \p NULL or the empty string, return \p NULL.
250 * Otherwise, Make a copy of \a name and return its directory component. Caller
251 * is responsible to free the result.
253 __must_check __malloc char *para_dirname(const char *name)
259 ret = para_strdup(name);
260 p = strrchr(ret, '/');
269 * Paraslash's version of basename().
271 * \param name Pointer to the full path.
273 * Compute the filename component of \a name.
275 * \return \p NULL if (a) \a name is the empty string or \p NULL, or (b) name
276 * ends with a slash. Otherwise, a pointer within \a name is returned. Caller
277 * must not free the result.
279 __must_check char *para_basename(const char *name)
285 ret = strrchr(name, '/');
293 * Cut trailing newline.
295 * \param buf The string to be chopped.
297 * Replace the last character in \p buf by zero if it is equal to
298 * the newline character.
306 if (buf[n - 1] == '\n')
311 * Get the logname of the current user.
313 * \return A dynamically allocated string that must be freed by the caller. On
314 * errors, the string "unknown_user" is returned, i.e. this function never
319 __must_check __malloc char *para_logname(void)
321 struct passwd *pw = getpwuid(getuid());
322 return para_strdup(pw? pw->pw_name : "unknown_user");
326 * Get the home directory of the current user.
328 * \return A dynamically allocated string that must be freed by the caller. If
329 * the home directory could not be found, this function returns "/tmp".
331 __must_check __malloc char *para_homedir(void)
333 struct passwd *pw = getpwuid(getuid());
334 return para_strdup(pw? pw->pw_dir : "/tmp");
338 * Get the own hostname.
340 * \return A dynamically allocated string containing the hostname.
344 __malloc char *para_hostname(void)
349 return para_strdup(u.nodename);
353 * Call a custom function for each complete line.
355 * \param flags Any combination of flags defined in \ref for_each_line_flags.
356 * \param buf The buffer containing data separated by newlines.
357 * \param size The number of bytes in \a buf.
358 * \param line_handler The custom function.
359 * \param private_data Pointer passed to \a line_handler.
361 * For each complete line in \p buf, \p line_handler is called. The first
362 * argument to \p line_handler is (a copy of) the current line, and \p
363 * private_data is passed as the second argument. If the \p FELF_READ_ONLY
364 * flag is unset, a pointer into \a buf is passed to the line handler,
365 * otherwise a pointer to a copy of the current line is passed instead. This
366 * copy is freed immediately after the line handler returns.
368 * The function returns if \p line_handler returns a negative value or no more
369 * lines are in the buffer. The rest of the buffer (last chunk containing an
370 * incomplete line) is moved to the beginning of the buffer if FELF_READ_ONLY is
373 * \return On success this function returns the number of bytes not handled to
374 * \p line_handler. The only possible error is a negative return value from the
375 * line handler. In this case processing stops and the return value of the line
376 * handler is returned to indicate failure.
378 * \sa \ref for_each_line_flags.
380 int for_each_line(unsigned flags, char *buf, size_t size,
381 line_handler_t *line_handler, void *private_data)
383 char *start = buf, *end;
384 int ret, i, num_lines = 0;
386 // PARA_NOTICE_LOG("buf: %s\n", buf);
387 while (start < buf + size) {
391 next_cr = memchr(start, '\n', buf + size - start);
392 next_null = memchr(start, '\0', buf + size - start);
393 if (!next_cr && !next_null)
395 if (next_cr && next_null) {
396 end = next_cr < next_null? next_cr : next_null;
397 } else if (next_null) {
402 if (!(flags & FELF_DISCARD_FIRST) || start != buf) {
403 if (flags & FELF_READ_ONLY) {
404 size_t s = end - start;
405 char *b = para_malloc(s + 1);
408 ret = line_handler(b, private_data);
412 ret = line_handler(start, private_data);
419 i = buf + size - start;
420 if (i && i != size && !(flags & FELF_READ_ONLY))
421 memmove(buf, start, i);
425 /** Return the hex characters of the lower 4 bits. */
426 #define hex(a) (hexchar[(a) & 15])
428 static void write_size_header(char *buf, int n)
430 static char hexchar[] = "0123456789abcdef";
432 buf[0] = hex(n >> 12);
433 buf[1] = hex(n >> 8);
434 buf[2] = hex(n >> 4);
440 * Read a four-byte hex-number and return its value.
442 * Each status item sent by para_server is prefixed with such a hex number in
443 * ASCII which describes the size of the status item.
445 * \param buf The buffer which must be at least four bytes long.
447 * \return The value of the hex number on success, \p -E_SIZE_PREFIX if the
448 * buffer did not contain only hex digits.
450 int read_size_header(const char *buf)
454 for (i = 0; i < 4; i++) {
455 unsigned char c = buf[i];
457 if (c >= '0' && c <= '9') {
461 if (c >= 'a' && c <= 'f') {
465 return -E_SIZE_PREFIX;
468 return -E_SIZE_PREFIX;
473 * Safely print into a buffer at a given offset.
475 * \param b Determines the buffer, its size, and the offset.
476 * \param fmt The format string.
478 * This function prints into the buffer given by \a b at the offset which is
479 * also given by \a b. If there is not enough space to hold the result, the
480 * buffer size is doubled until the underlying call to vsnprintf() succeeds
481 * or the size of the buffer exceeds the maximal size specified in \a b.
483 * In the latter case the unmodified \a buf and \a offset values as well as the
484 * private_data pointer of \a b are passed to the \a max_size_handler of \a b.
485 * If this function succeeds, i.e. returns a non-negative value, the offset of
486 * \a b is reset to zero and the given data is written to the beginning of the
487 * buffer. If \a max_size_handler() returns a negative value, this value is
488 * returned by \a para_printf().
490 * Upon return, the offset of \a b is adjusted accordingly so that subsequent
491 * calls to this function append data to what is already contained in the
494 * It's OK to call this function with \p b->buf being \p NULL. In this case, an
495 * initial buffer is allocated.
497 * \return The number of bytes printed into the buffer (not including the
498 * terminating \p NULL byte) on success, negative on errors. If there is no
499 * size-bound on \a b, i.e. if \p b->max_size is zero, this function never
502 * \sa make_message(), vsnprintf(3).
504 __printf_2_3 int para_printf(struct para_buffer *b, const char *fmt, ...)
506 int ret, sz_off = (b->flags & PBF_SIZE_PREFIX)? 5 : 0;
509 b->buf = para_malloc(128);
514 char *p = b->buf + b->offset;
515 size_t size = b->size - b->offset;
520 ret = vsnprintf(p + sz_off, size - sz_off, fmt, ap);
522 if (ret > -1 && ret < size - sz_off) { /* success */
523 b->offset += ret + sz_off;
525 write_size_header(p, ret);
529 /* check if we may grow the buffer */
530 if (!b->max_size || 2 * b->size < b->max_size) { /* yes */
531 /* try again with more space */
533 b->buf = para_realloc(b->buf, b->size);
536 /* can't grow buffer */
537 if (!b->offset || !b->max_size_handler) /* message too large */
538 return -ERRNO_TO_PARA_ERROR(ENOSPC);
539 ret = b->max_size_handler(b->buf, b->offset, b->private_data);
546 /** \cond llong_minmax */
547 /* LLONG_MAX and LLONG_MIN might not be defined. */
549 #define LLONG_MAX 9223372036854775807LL
552 #define LLONG_MIN (-LLONG_MAX - 1LL)
554 /** \endcond llong_minmax */
557 * Convert a string to a 64-bit signed integer value.
559 * \param str The string to be converted.
560 * \param value Result pointer.
564 * \sa para_atoi32(), strtol(3), atoi(3).
566 int para_atoi64(const char *str, int64_t *value)
571 errno = 0; /* To distinguish success/failure after call */
572 tmp = strtoll(str, &endptr, 10);
573 if (errno == ERANGE && (tmp == LLONG_MAX || tmp == LLONG_MIN))
574 return -E_ATOI_OVERFLOW;
575 if (errno != 0 && tmp == 0) /* other error */
578 return -E_ATOI_NO_DIGITS;
579 if (*endptr != '\0') /* Further characters after number */
580 return -E_ATOI_JUNK_AT_END;
586 * Convert a string to a 32-bit signed integer value.
588 * \param str The string to be converted.
589 * \param value Result pointer.
595 int para_atoi32(const char *str, int32_t *value)
599 const int32_t max = 2147483647;
601 ret = para_atoi64(str, &tmp);
604 if (tmp > max || tmp < -max - 1)
605 return -E_ATOI_OVERFLOW;
610 static inline int loglevel_equal(const char *arg, const char * const ll)
612 return !strncasecmp(arg, ll, strlen(ll));
616 * Compute the loglevel number from its name.
618 * \param txt The name of the loglevel (debug, info, ...).
620 * \return The numeric representation of the loglevel name.
622 int get_loglevel_by_name(const char *txt)
624 if (loglevel_equal(txt, "debug"))
626 if (loglevel_equal(txt, "info"))
628 if (loglevel_equal(txt, "notice"))
630 if (loglevel_equal(txt, "warning"))
632 if (loglevel_equal(txt, "error"))
634 if (loglevel_equal(txt, "crit"))
636 if (loglevel_equal(txt, "emerg"))
641 static int get_next_word(const char *buf, const char *delim, char **word)
643 enum line_state_flags {LSF_HAVE_WORD = 1, LSF_BACKSLASH = 2,
644 LSF_SINGLE_QUOTE = 4, LSF_DOUBLE_QUOTE = 8};
649 out = para_malloc(strlen(buf) + 1);
652 for (in = buf; *in; in++) {
657 if (state & LSF_BACKSLASH) /* \\ */
659 state |= LSF_BACKSLASH;
660 state |= LSF_HAVE_WORD;
664 if (state & LSF_BACKSLASH) { /* \n or \t */
665 *out++ = (*in == 'n')? '\n' : '\t';
666 state &= ~LSF_BACKSLASH;
671 if (state & LSF_BACKSLASH) /* \" */
673 if (state & LSF_SINGLE_QUOTE) /* '" */
675 if (state & LSF_DOUBLE_QUOTE) {
676 state &= ~LSF_DOUBLE_QUOTE;
679 state |= LSF_HAVE_WORD;
680 state |= LSF_DOUBLE_QUOTE;
683 if (state & LSF_BACKSLASH) /* \' */
685 if (state & LSF_DOUBLE_QUOTE) /* "' */
687 if (state & LSF_SINGLE_QUOTE) {
688 state &= ~LSF_SINGLE_QUOTE;
691 state |= LSF_HAVE_WORD;
692 state |= LSF_SINGLE_QUOTE;
695 for (p = delim; *p; p++) {
698 if (state & LSF_BACKSLASH)
700 if (state & LSF_SINGLE_QUOTE)
702 if (state & LSF_DOUBLE_QUOTE)
704 if (state & LSF_HAVE_WORD)
708 if (*p) /* ignore delimiter at the beginning */
711 state |= LSF_HAVE_WORD;
713 state &= ~LSF_BACKSLASH;
716 if (!(state & LSF_HAVE_WORD))
718 ret = -ERRNO_TO_PARA_ERROR(EINVAL);
719 if (state & LSF_BACKSLASH) {
720 PARA_ERROR_LOG("trailing backslash\n");
723 if ((state & LSF_SINGLE_QUOTE) || (state & LSF_DOUBLE_QUOTE)) {
724 PARA_ERROR_LOG("unmatched quote character\n");
737 * Get the number of the word the cursor is on.
739 * \param buf The zero-terminated line buffer.
740 * \param delim Characters that separate words.
741 * \param point The cursor position.
743 * \return Zero-based word number.
745 int compute_word_num(const char *buf, const char *delim, int point)
751 for (p = buf, num_words = 0; ; p += ret, num_words++) {
752 ret = get_next_word(p, delim, &word);
756 if (p + ret >= buf + point)
763 * Free an array of words created by create_argv() or create_shifted_argv().
765 * \param argv A pointer previously obtained by \ref create_argv().
767 void free_argv(char **argv)
773 for (i = 0; argv[i]; i++)
778 static int create_argv_offset(int offset, const char *buf, const char *delim,
781 char *word, **argv = para_malloc((offset + 1) * sizeof(char *));
785 for (i = 0; i < offset; i++)
787 for (p = buf; p && *p; p += ret, i++) {
788 ret = get_next_word(p, delim, &word);
793 argv = para_realloc(argv, (i + 2) * sizeof(char*));
808 * Split a buffer into words.
810 * This parser honors single and double quotes, backslash-escaped characters
811 * and special characters like \p \\n. The result contains pointers to copies
812 * of the words contained in \a buf and has to be freed by using \ref
815 * \param buf The buffer to be split.
816 * \param delim Each character in this string is treated as a separator.
817 * \param result The array of words is returned here.
819 * \return Number of words in \a buf, negative on errors.
821 int create_argv(const char *buf, const char *delim, char ***result)
823 return create_argv_offset(0, buf, delim, result);
827 * Split a buffer into words, offset one.
829 * This is similar to \ref create_argv() but the returned array is one element
830 * larger, words start at index one and element zero is initialized to \p NULL.
831 * Callers must set element zero to a non-NULL value before calling free_argv()
832 * on the returned array to avoid a memory leak.
834 * \param buf See \ref create_argv().
835 * \param delim See \ref create_argv().
836 * \param result See \ref create_argv().
838 * \return Number of words plus one on success, negative on errors.
840 int create_shifted_argv(const char *buf, const char *delim, char ***result)
842 return create_argv_offset(1, buf, delim, result);
846 * Find out if the given string is contained in the arg vector.
848 * \param arg The string to look for.
849 * \param argv The array to search.
851 * \return The first index whose value equals \a arg, or \p -E_ARG_NOT_FOUND if
852 * arg was not found in \a argv.
854 int find_arg(const char *arg, char **argv)
859 return -E_ARG_NOT_FOUND;
860 for (i = 0; argv[i]; i++)
861 if (strcmp(arg, argv[i]) == 0)
863 return -E_ARG_NOT_FOUND;
867 * Compile a regular expression.
869 * This simple wrapper calls regcomp() and logs a message on errors.
871 * \param preg See regcomp(3).
872 * \param regex See regcomp(3).
873 * \param cflags See regcomp(3).
877 int para_regcomp(regex_t *preg, const char *regex, int cflags)
881 int ret = regcomp(preg, regex, cflags);
885 size = regerror(ret, preg, NULL, 0);
886 buf = para_malloc(size);
887 regerror(ret, preg, buf, size);
888 PARA_ERROR_LOG("%s\n", buf);
894 * strdup() for not necessarily zero-terminated strings.
896 * \param src The source buffer.
897 * \param len The number of bytes to be copied.
899 * \return A 0-terminated buffer of length \a len + 1.
901 * This is similar to strndup(), which is a GNU extension. However, one
902 * difference is that strndup() returns \p NULL if insufficient memory was
903 * available while this function aborts in this case.
905 * \sa strdup(), \ref para_strdup().
907 char *safe_strdup(const char *src, size_t len)
911 assert(len < (size_t)-1);
912 p = para_malloc(len + 1);
920 * Copy the value of a key=value pair.
922 * This checks whether the given buffer starts with "key=", ignoring case. If
923 * yes, a copy of the value is returned. The source buffer may not be
926 * \param src The source buffer.
927 * \param len The number of bytes of the tag.
928 * \param key Only copy if it is the value of this key.
930 * \return A zero-terminated buffer, or \p NULL if the key was
931 * not of the given type.
933 char *key_value_copy(const char *src, size_t len, const char *key)
935 int keylen = strlen(key);
939 if (strncasecmp(src, key, keylen))
941 if (src[keylen] != '=')
943 return safe_strdup(src + keylen + 1, len - keylen - 1);