/*
- * Copyright (C) 2004-2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2004 Andre Noll <maan@tuebingen.mpg.de>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
/** \file string.c Memory allocation and string handling functions. */
-#include "para.h"
-#include "string.h"
+#define _GNU_SOURCE
-#include <sys/time.h> /* gettimeofday */
#include <pwd.h>
#include <sys/utsname.h> /* uname() */
+
#include <string.h>
+#include <regex.h>
+#include <langinfo.h>
+#include <wchar.h>
+#include <wctype.h>
+
+#include "para.h"
+#include "string.h"
#include "error.h"
/**
* A wrapper for realloc(3). It calls \p exit(\p EXIT_FAILURE) on errors,
* i.e. there is no need to check the return value in the caller.
*
- * \return A pointer to the newly allocated memory, which is suitably aligned
- * for any kind of variable and may be different from \a p.
+ * \return A pointer to newly allocated memory which is suitably aligned for
+ * any kind of variable and may be different from \a p.
*
* \sa realloc(3).
*/
-__must_check __malloc void *para_realloc(void *p, size_t size)
+__must_check void *para_realloc(void *p, size_t size)
{
/*
* No need to check for NULL pointers: If p is NULL, the call
exit(EXIT_FAILURE);
}
+/**
+ * Print a formated message to a dynamically allocated string.
+ *
+ * \param result The formated string is returned here.
+ * \param fmt The format string.
+ * \param ap Initialized list of arguments.
+ *
+ * This function is similar to vasprintf(), a GNU extension which is not in C
+ * or POSIX. It allocates a string large enough to hold the output including
+ * the terminating null byte. The allocated string is returned via the first
+ * argument and must be freed by the caller. However, unlike vasprintf(), this
+ * function calls exit() if insufficient memory is available, while vasprintf()
+ * returns -1 in this case.
+ *
+ * \return Number of bytes written, not including the terminating \p NULL
+ * character.
+ *
+ * \sa printf(3), vsnprintf(3), va_start(3), vasprintf(3), \ref xasprintf().
+ */
+__printf_2_0 unsigned xvasprintf(char **result, const char *fmt, va_list ap)
+{
+ int ret;
+ size_t size = 150;
+ va_list aq;
+
+ *result = para_malloc(size + 1);
+ va_copy(aq, ap);
+ ret = vsnprintf(*result, size, fmt, aq);
+ va_end(aq);
+ assert(ret >= 0);
+ if (ret < size) /* OK */
+ return ret;
+ size = ret + 1;
+ *result = para_realloc(*result, size);
+ va_copy(aq, ap);
+ ret = vsnprintf(*result, size, fmt, aq);
+ va_end(aq);
+ assert(ret >= 0 && ret < size);
+ return ret;
+}
+
+/**
+ * Print to a dynamically allocated string, variable number of arguments.
+ *
+ * \param result See \ref xvasprintf().
+ * \param fmt Usual format string.
+ *
+ * \return The return value of the underlying call to \ref xvasprintf().
+ *
+ * \sa \ref xvasprintf() and the references mentioned there.
+ */
+__printf_2_3 unsigned xasprintf(char **result, const char *fmt, ...)
+{
+ va_list ap;
+ unsigned ret;
+
+ va_start(ap, fmt);
+ ret = xvasprintf(result, fmt, ap);
+ va_end(ap);
+ return ret;
+}
+
/**
* Allocate a sufficiently large string and print into it.
*
* \return This function either returns a pointer to a string that must be
* freed by the caller or aborts without returning.
*
- * \sa printf(3).
+ * \sa printf(3), xasprintf().
*/
__must_check __printf_1_2 __malloc char *make_message(const char *fmt, ...)
{
char *msg;
+ va_list ap;
- PARA_VSPRINTF(fmt, msg);
+ va_start(ap, fmt);
+ xvasprintf(&msg, fmt, ap);
+ va_end(ap);
return msg;
}
+/**
+ * Free the content of a pointer and set it to \p NULL.
+ *
+ * This is equivalent to "free(*arg); *arg = NULL;".
+ *
+ * \param arg The pointer whose content should be freed.
+ */
+void freep(void *arg)
+{
+ void **ptr = (void **)arg;
+ free(*ptr);
+ *ptr = NULL;
+}
+
/**
* Paraslash's version of strcat().
*
* ends with a slash. Otherwise, a pointer within \a name is returned. Caller
* must not free the result.
*/
-__must_check const char *para_basename(const char *name)
+__must_check char *para_basename(const char *name)
{
- const char *ret;
+ char *ret;
if (!name || !*name)
return NULL;
ret = strrchr(name, '/');
if (!ret)
- return name;
+ return (char *)name;
ret++;
return ret;
}
-/**
- * Cut trailing newline.
- *
- * \param buf The string to be chopped.
- *
- * Replace the last character in \p buf by zero if it is equal to
- * the newline character.
- */
-void chop(char *buf)
-{
- int n = strlen(buf);
-
- if (!n)
- return;
- if (buf[n - 1] == '\n')
- buf[n - 1] = '\0';
-}
-
-/**
- * Get a random filename.
- *
- * This is by no means a secure way to create temporary files in a hostile
- * directory like \p /tmp. However, it is OK to use for temp files, fifos,
- * sockets that are created in ~/.paraslash. Result must be freed by the
- * caller.
- *
- * \return A pointer to a random filename.
- */
-__must_check __malloc char *para_tmpname(void)
-{
- struct timeval now;
- unsigned int seed;
-
- gettimeofday(&now, NULL);
- seed = now.tv_usec;
- srand(seed);
- return make_message("%08i", rand());
-}
-
/**
* Get the logname of the current user.
*
return para_strdup(pw? pw->pw_dir : "/tmp");
}
-/**
- * Split string and return pointers to its parts.
- *
- * \param args The string to be split.
- * \param argv_ptr Pointer to the list of substrings.
- * \param delim Delimiter.
- *
- * This function modifies \a args by replacing each occurrence of \a delim by
- * zero. A \p NULL-terminated array of pointers to char* is allocated dynamically
- * and these pointers are initialized to point to the broken-up substrings
- * within \a args. A pointer to this array is returned via \a argv_ptr.
- *
- * \return The number of substrings found in \a args.
- */
-unsigned split_args(char *args, char *** const argv_ptr, const char *delim)
-{
- char *p;
- char **argv;
- size_t n = 0, i, j;
-
- p = args + strspn(args, delim);
- for (;;) {
- i = strcspn(p, delim);
- if (!i)
- break;
- p += i;
- n++;
- p += strspn(p, delim);
- }
- *argv_ptr = para_malloc((n + 1) * sizeof(char *));
- argv = *argv_ptr;
- i = 0;
- p = args + strspn(args, delim);
- while (p) {
- argv[i] = p;
- j = strcspn(p, delim);
- if (!j)
- break;
- p += strcspn(p, delim);
- if (*p) {
- *p = '\0';
- p++;
- p += strspn(p, delim);
- }
- i++;
- }
- argv[n] = NULL;
- return n;
-}
-
/**
* Get the own hostname.
*
}
/**
- * Used to distinguish between read-only and read-write mode.
+ * Call a custom function for each complete line.
*
- * \sa for_each_line(), for_each_line_ro().
+ * \param flags Any combination of flags defined in \ref for_each_line_flags.
+ * \param buf The buffer containing data separated by newlines.
+ * \param size The number of bytes in \a buf.
+ * \param line_handler The custom function.
+ * \param private_data Pointer passed to \a line_handler.
+ *
+ * For each complete line in \p buf, \p line_handler is called. The first
+ * argument to \p line_handler is (a copy of) the current line, and \p
+ * private_data is passed as the second argument. If the \p FELF_READ_ONLY
+ * flag is unset, a pointer into \a buf is passed to the line handler,
+ * otherwise a pointer to a copy of the current line is passed instead. This
+ * copy is freed immediately after the line handler returns.
+ *
+ * The function returns if \p line_handler returns a negative value or no more
+ * lines are in the buffer. The rest of the buffer (last chunk containing an
+ * incomplete line) is moved to the beginning of the buffer if FELF_READ_ONLY is
+ * unset.
+ *
+ * \return On success this function returns the number of bytes not handled to
+ * \p line_handler. The only possible error is a negative return value from the
+ * line handler. In this case processing stops and the return value of the line
+ * handler is returned to indicate failure.
+ *
+ * \sa \ref for_each_line_flags.
*/
-enum for_each_line_modes{
- /** Activate read-only mode. */
- LINE_MODE_RO,
- /** Activate read-write mode. */
- LINE_MODE_RW
-};
-
-static int for_each_complete_line(enum for_each_line_modes mode, char *buf,
- size_t size, line_handler_t *line_handler, void *private_data)
+int for_each_line(unsigned flags, char *buf, size_t size,
+ line_handler_t *line_handler, void *private_data)
{
char *start = buf, *end;
int ret, i, num_lines = 0;
char *next_cr;
next_cr = memchr(start, '\n', buf + size - start);
- next_null = memchr(start, '\0', buf + size - start);
+ next_null = memchr(start, '\0', next_cr?
+ next_cr - start : buf + size - start);
if (!next_cr && !next_null)
break;
- if (next_cr && next_null) {
- end = next_cr < next_null? next_cr : next_null;
- } else if (next_null) {
+ if (next_null)
end = next_null;
- } else
+ else
end = next_cr;
num_lines++;
- if (!line_handler) {
- start = ++end;
- continue;
- }
- if (mode == LINE_MODE_RO) {
- size_t s = end - start;
- char *b = para_malloc(s + 1);
- memcpy(b, start, s);
- b[s] = '\0';
-// PARA_NOTICE_LOG("b: %s, start: %s\n", b, start);
- ret = line_handler(b, private_data);
- free(b);
- } else {
- *end = '\0';
- ret = line_handler(start, private_data);
+ if (!(flags & FELF_DISCARD_FIRST) || start != buf) {
+ if (flags & FELF_READ_ONLY) {
+ size_t s = end - start;
+ char *b = para_malloc(s + 1);
+ memcpy(b, start, s);
+ b[s] = '\0';
+ ret = line_handler(b, private_data);
+ free(b);
+ } else {
+ *end = '\0';
+ ret = line_handler(start, private_data);
+ }
+ if (ret < 0)
+ return ret;
}
- if (ret < 0)
- return ret;
start = ++end;
}
- if (!line_handler || mode == LINE_MODE_RO)
- return num_lines;
i = buf + size - start;
- if (i && i != size)
+ if (i && i != size && !(flags & FELF_READ_ONLY))
memmove(buf, start, i);
return i;
}
-/**
- * Call a custom function for each complete line.
- *
- * \param buf The buffer containing data separated by newlines.
- * \param size The number of bytes in \a buf.
- * \param line_handler The custom function.
- * \param private_data Pointer passed to \a line_handler.
- *
- * If \p line_handler is \p NULL, the function returns the number of complete
- * lines in \p buf. Otherwise, \p line_handler is called for each complete
- * line in \p buf. The first argument to \p line_handler is the current line,
- * and \p private_data is passed as the second argument. The function returns
- * if \p line_handler returns a negative value or no more lines are in the
- * buffer. The rest of the buffer (last chunk containing an incomplete line)
- * is moved to the beginning of the buffer.
- *
- * \return If \p line_handler is not \p NULL, this function returns the number
- * of bytes not handled to \p line_handler on success, or the negative return
- * value of the \p line_handler on errors.
- *
- * \sa for_each_line_ro().
- */
-int for_each_line(char *buf, size_t size, line_handler_t *line_handler,
- void *private_data)
+/** Return the hex characters of the lower 4 bits. */
+#define hex(a) (hexchar[(a) & 15])
+
+static void write_size_header(char *buf, int n)
{
- return for_each_complete_line(LINE_MODE_RW, buf, size, line_handler,
- private_data);
+ static char hexchar[] = "0123456789abcdef";
+
+ buf[0] = hex(n >> 12);
+ buf[1] = hex(n >> 8);
+ buf[2] = hex(n >> 4);
+ buf[3] = hex(n);
+ buf[4] = ' ';
}
/**
- * Call a custom function for each complete line.
- *
- * \param buf Same meaning as in \p for_each_line().
- * \param size Same meaning as in \p for_each_line().
- * \param line_handler Same meaning as in \p for_each_line().
- * \param private_data Same meaning as in \p for_each_line().
+ * Read a four-byte hex-number and return its value.
*
- * This function behaves like \p for_each_line(), but \a buf is left unchanged.
+ * Each status item sent by para_server is prefixed with such a hex number in
+ * ASCII which describes the size of the status item.
*
- * \return On success, the function returns the number of complete lines in \p
- * buf, otherwise the (negative) return value of \p line_handler is returned.
+ * \param buf The buffer which must be at least four bytes long.
*
- * \sa for_each_line().
+ * \return The value of the hex number on success, \p -E_SIZE_PREFIX if the
+ * buffer did not contain only hex digits.
*/
-int for_each_line_ro(char *buf, size_t size, line_handler_t *line_handler,
- void *private_data)
+int read_size_header(const char *buf)
{
- return for_each_complete_line(LINE_MODE_RO, buf, size, line_handler,
- private_data);
+ int i, len = 0;
+
+ for (i = 0; i < 4; i++) {
+ unsigned char c = buf[i];
+ len <<= 4;
+ if (c >= '0' && c <= '9') {
+ len += c - '0';
+ continue;
+ }
+ if (c >= 'a' && c <= 'f') {
+ len += c - 'a' + 10;
+ continue;
+ }
+ return -E_SIZE_PREFIX;
+ }
+ if (buf[4] != ' ')
+ return -E_SIZE_PREFIX;
+ return len;
}
/**
* private_data pointer of \a b are passed to the \a max_size_handler of \a b.
* If this function succeeds, i.e. returns a non-negative value, the offset of
* \a b is reset to zero and the given data is written to the beginning of the
- * buffer.
+ * buffer. If \a max_size_handler() returns a negative value, this value is
+ * returned by \a para_printf().
*
* Upon return, the offset of \a b is adjusted accordingly so that subsequent
* calls to this function append data to what is already contained in the
* initial buffer is allocated.
*
* \return The number of bytes printed into the buffer (not including the
- * terminating \p NULL byte).
+ * terminating \p NULL byte) on success, negative on errors. If there is no
+ * size-bound on \a b, i.e. if \p b->max_size is zero, this function never
+ * fails.
*
* \sa make_message(), vsnprintf(3).
*/
__printf_2_3 int para_printf(struct para_buffer *b, const char *fmt, ...)
{
- int ret;
+ int ret, sz_off = (b->flags & PBF_SIZE_PREFIX)? 5 : 0;
if (!b->buf) {
b->buf = para_malloc(128);
char *p = b->buf + b->offset;
size_t size = b->size - b->offset;
va_list ap;
- if (size) {
+
+ if (size > sz_off) {
va_start(ap, fmt);
- ret = vsnprintf(p, size, fmt, ap);
+ ret = vsnprintf(p + sz_off, size - sz_off, fmt, ap);
va_end(ap);
- if (ret > -1 && ret < size) { /* success */
- b->offset += ret;
- return ret;
+ if (ret > -1 && ret < size - sz_off) { /* success */
+ b->offset += ret + sz_off;
+ if (sz_off)
+ write_size_header(p, ret);
+ return ret + sz_off;
}
}
/* check if we may grow the buffer */
}
}
-/** \cond LLONG_MAX and LLONG_MIN might not be defined. */
+/** \cond llong_minmax */
+/* LLONG_MAX and LLONG_MIN might not be defined. */
#ifndef LLONG_MAX
#define LLONG_MAX 9223372036854775807LL
#endif
#ifndef LLONG_MIN
#define LLONG_MIN (-LLONG_MAX - 1LL)
#endif
-/** \endcond */
+/** \endcond llong_minmax */
/**
* Convert a string to a 64-bit signed integer value.
return LL_EMERG;
return -1;
}
+
+static int get_next_word(const char *buf, const char *delim, char **word)
+{
+ enum line_state_flags {LSF_HAVE_WORD = 1, LSF_BACKSLASH = 2,
+ LSF_SINGLE_QUOTE = 4, LSF_DOUBLE_QUOTE = 8};
+ const char *in;
+ char *out;
+ int ret, state = 0;
+
+ out = para_malloc(strlen(buf) + 1);
+ *out = '\0';
+ *word = out;
+ for (in = buf; *in; in++) {
+ const char *p;
+
+ switch (*in) {
+ case '\\':
+ if (state & LSF_BACKSLASH) /* \\ */
+ goto copy_char;
+ state |= LSF_BACKSLASH;
+ state |= LSF_HAVE_WORD;
+ continue;
+ case 'n':
+ case 't':
+ if (state & LSF_BACKSLASH) { /* \n or \t */
+ *out++ = (*in == 'n')? '\n' : '\t';
+ state &= ~LSF_BACKSLASH;
+ continue;
+ }
+ goto copy_char;
+ case '"':
+ if (state & LSF_BACKSLASH) /* \" */
+ goto copy_char;
+ if (state & LSF_SINGLE_QUOTE) /* '" */
+ goto copy_char;
+ if (state & LSF_DOUBLE_QUOTE) {
+ state &= ~LSF_DOUBLE_QUOTE;
+ continue;
+ }
+ state |= LSF_HAVE_WORD;
+ state |= LSF_DOUBLE_QUOTE;
+ continue;
+ case '\'':
+ if (state & LSF_BACKSLASH) /* \' */
+ goto copy_char;
+ if (state & LSF_DOUBLE_QUOTE) /* "' */
+ goto copy_char;
+ if (state & LSF_SINGLE_QUOTE) {
+ state &= ~LSF_SINGLE_QUOTE;
+ continue;
+ }
+ state |= LSF_HAVE_WORD;
+ state |= LSF_SINGLE_QUOTE;
+ continue;
+ }
+ for (p = delim; *p; p++) {
+ if (*in != *p)
+ continue;
+ if (state & LSF_BACKSLASH)
+ goto copy_char;
+ if (state & LSF_SINGLE_QUOTE)
+ goto copy_char;
+ if (state & LSF_DOUBLE_QUOTE)
+ goto copy_char;
+ if (state & LSF_HAVE_WORD)
+ goto success;
+ break;
+ }
+ if (*p) /* ignore delimiter at the beginning */
+ continue;
+copy_char:
+ state |= LSF_HAVE_WORD;
+ *out++ = *in;
+ state &= ~LSF_BACKSLASH;
+ }
+ ret = 0;
+ if (!(state & LSF_HAVE_WORD))
+ goto out;
+ ret = -ERRNO_TO_PARA_ERROR(EINVAL);
+ if (state & LSF_BACKSLASH) {
+ PARA_ERROR_LOG("trailing backslash\n");
+ goto out;
+ }
+ if ((state & LSF_SINGLE_QUOTE) || (state & LSF_DOUBLE_QUOTE)) {
+ PARA_ERROR_LOG("unmatched quote character\n");
+ goto out;
+ }
+success:
+ *out = '\0';
+ return in - buf;
+out:
+ free(*word);
+ *word = NULL;
+ return ret;
+}
+
+/**
+ * Get the number of the word the cursor is on.
+ *
+ * \param buf The zero-terminated line buffer.
+ * \param delim Characters that separate words.
+ * \param point The cursor position.
+ *
+ * \return Zero-based word number.
+ */
+int compute_word_num(const char *buf, const char *delim, int point)
+{
+ int ret, num_words;
+ const char *p;
+ char *word;
+
+ for (p = buf, num_words = 0; ; p += ret, num_words++) {
+ ret = get_next_word(p, delim, &word);
+ if (ret <= 0)
+ break;
+ free(word);
+ if (p + ret >= buf + point)
+ break;
+ }
+ return num_words;
+}
+
+/**
+ * Free an array of words created by create_argv() or create_shifted_argv().
+ *
+ * \param argv A pointer previously obtained by \ref create_argv().
+ */
+void free_argv(char **argv)
+{
+ int i;
+
+ if (!argv)
+ return;
+ for (i = 0; argv[i]; i++)
+ free(argv[i]);
+ free(argv);
+}
+
+static int create_argv_offset(int offset, const char *buf, const char *delim,
+ char ***result)
+{
+ char *word, **argv = para_malloc((offset + 1) * sizeof(char *));
+ const char *p;
+ int i, ret;
+
+ for (i = 0; i < offset; i++)
+ argv[i] = NULL;
+ for (p = buf; p && *p; p += ret, i++) {
+ ret = get_next_word(p, delim, &word);
+ if (ret < 0)
+ goto err;
+ if (!ret)
+ break;
+ argv = para_realloc(argv, (i + 2) * sizeof(char*));
+ argv[i] = word;
+ }
+ argv[i] = NULL;
+ *result = argv;
+ return i;
+err:
+ while (i > 0)
+ free(argv[--i]);
+ free(argv);
+ *result = NULL;
+ return ret;
+}
+
+/**
+ * Split a buffer into words.
+ *
+ * This parser honors single and double quotes, backslash-escaped characters
+ * and special characters like \p \\n. The result contains pointers to copies
+ * of the words contained in \a buf and has to be freed by using \ref
+ * free_argv().
+ *
+ * \param buf The buffer to be split.
+ * \param delim Each character in this string is treated as a separator.
+ * \param result The array of words is returned here.
+ *
+ * \return Number of words in \a buf, negative on errors.
+ */
+int create_argv(const char *buf, const char *delim, char ***result)
+{
+ return create_argv_offset(0, buf, delim, result);
+}
+
+/**
+ * Split a buffer into words, offset one.
+ *
+ * This is similar to \ref create_argv() but the returned array is one element
+ * larger, words start at index one and element zero is initialized to \p NULL.
+ * Callers must set element zero to a non-NULL value before calling free_argv()
+ * on the returned array to avoid a memory leak.
+ *
+ * \param buf See \ref create_argv().
+ * \param delim See \ref create_argv().
+ * \param result See \ref create_argv().
+ *
+ * \return Number of words plus one on success, negative on errors.
+ */
+int create_shifted_argv(const char *buf, const char *delim, char ***result)
+{
+ return create_argv_offset(1, buf, delim, result);
+}
+
+/**
+ * Find out if the given string is contained in the arg vector.
+ *
+ * \param arg The string to look for.
+ * \param argv The array to search.
+ *
+ * \return The first index whose value equals \a arg, or \p -E_ARG_NOT_FOUND if
+ * arg was not found in \a argv.
+ */
+int find_arg(const char *arg, char **argv)
+{
+ int i;
+
+ if (!argv)
+ return -E_ARG_NOT_FOUND;
+ for (i = 0; argv[i]; i++)
+ if (strcmp(arg, argv[i]) == 0)
+ return i;
+ return -E_ARG_NOT_FOUND;
+}
+
+/**
+ * Compile a regular expression.
+ *
+ * This simple wrapper calls regcomp() and logs a message on errors.
+ *
+ * \param preg See regcomp(3).
+ * \param regex See regcomp(3).
+ * \param cflags See regcomp(3).
+ *
+ * \return Standard.
+ */
+int para_regcomp(regex_t *preg, const char *regex, int cflags)
+{
+ char *buf;
+ size_t size;
+ int ret = regcomp(preg, regex, cflags);
+
+ if (ret == 0)
+ return 1;
+ size = regerror(ret, preg, NULL, 0);
+ buf = para_malloc(size);
+ regerror(ret, preg, buf, size);
+ PARA_ERROR_LOG("%s\n", buf);
+ free(buf);
+ return -E_REGEX;
+}
+
+/**
+ * strdup() for not necessarily zero-terminated strings.
+ *
+ * \param src The source buffer.
+ * \param len The number of bytes to be copied.
+ *
+ * \return A 0-terminated buffer of length \a len + 1.
+ *
+ * This is similar to strndup(), which is a GNU extension. However, one
+ * difference is that strndup() returns \p NULL if insufficient memory was
+ * available while this function aborts in this case.
+ *
+ * \sa strdup(), \ref para_strdup().
+ */
+char *safe_strdup(const char *src, size_t len)
+{
+ char *p;
+
+ assert(len < (size_t)-1);
+ p = para_malloc(len + 1);
+ if (len > 0)
+ memcpy(p, src, len);
+ p[len] = '\0';
+ return p;
+}
+
+/**
+ * Copy the value of a key=value pair.
+ *
+ * This checks whether the given buffer starts with "key=", ignoring case. If
+ * yes, a copy of the value is returned. The source buffer may not be
+ * zero-terminated.
+ *
+ * \param src The source buffer.
+ * \param len The number of bytes of the tag.
+ * \param key Only copy if it is the value of this key.
+ *
+ * \return A zero-terminated buffer, or \p NULL if the key was
+ * not of the given type.
+ */
+char *key_value_copy(const char *src, size_t len, const char *key)
+{
+ int keylen = strlen(key);
+
+ if (len <= keylen)
+ return NULL;
+ if (strncasecmp(src, key, keylen))
+ return NULL;
+ if (src[keylen] != '=')
+ return NULL;
+ return safe_strdup(src + keylen + 1, len - keylen - 1);
+}
+
+static bool utf8_mode(void)
+{
+ static bool initialized, have_utf8;
+
+ if (!initialized) {
+ char *info = nl_langinfo(CODESET);
+ have_utf8 = (info && strcmp(info, "UTF-8") == 0);
+ initialized = true;
+ PARA_INFO_LOG("%susing UTF-8 character encoding\n",
+ have_utf8? "" : "not ");
+ }
+ return have_utf8;
+}
+
+/*
+ * glibc's wcswidth returns -1 if the string contains a tab character, which
+ * makes the function next to useless. The two functions below are taken from
+ * mutt.
+ */
+
+#define IsWPrint(wc) (iswprint(wc) || wc >= 0xa0)
+
+static int mutt_wcwidth(wchar_t wc, size_t pos)
+{
+ int n;
+
+ if (wc == 0x09) /* tab */
+ return (pos | 7) + 1 - pos;
+ n = wcwidth(wc);
+ if (IsWPrint(wc) && n > 0)
+ return n;
+ if (!(wc & ~0x7f))
+ return 2;
+ if (!(wc & ~0xffff))
+ return 6;
+ return 10;
+}
+
+static size_t mutt_wcswidth(const wchar_t *s, size_t n)
+{
+ size_t w = 0;
+
+ while (n--)
+ w += mutt_wcwidth(*s++, w);
+ return w;
+}
+
+/**
+ * Skip a given number of cells at the beginning of a string.
+ *
+ * \param s The input string.
+ * \param cells_to_skip Desired number of cells that should be skipped.
+ * \param bytes_to_skip Result.
+ *
+ * This function computes how many input bytes must be skipped to advance a
+ * string by the given width. If the current character encoding is not UTF-8,
+ * this is simply the given number of cells, i.e. \a cells_to_skip. Otherwise,
+ * \a s is treated as a multibyte string and on successful return, \a s +
+ * bytes_to_skip points to the start of a multibyte string such that the total
+ * width of the multibyte characters that are skipped by advancing \a s that
+ * many bytes equals at least \a cells_to_skip.
+ *
+ * \return Standard.
+ */
+int skip_cells(const char *s, size_t cells_to_skip, size_t *bytes_to_skip)
+{
+ wchar_t wc;
+ mbstate_t ps;
+ size_t n, bytes_parsed, cells_skipped;
+
+ *bytes_to_skip = 0;
+ if (cells_to_skip == 0)
+ return 0;
+ if (!utf8_mode()) {
+ *bytes_to_skip = cells_to_skip;
+ return 0;
+ }
+ bytes_parsed = cells_skipped = 0;
+ memset(&ps, 0, sizeof(ps));
+ n = strlen(s);
+ while (cells_to_skip > cells_skipped) {
+ size_t mbret;
+
+ mbret = mbrtowc(&wc, s + bytes_parsed, n - bytes_parsed, &ps);
+ assert(mbret != 0);
+ if (mbret == (size_t)-1 || mbret == (size_t)-2)
+ return -ERRNO_TO_PARA_ERROR(EILSEQ);
+ bytes_parsed += mbret;
+ cells_skipped += mutt_wcwidth(wc, cells_skipped);
+ }
+ *bytes_to_skip = bytes_parsed;
+ return 1;
+}
+
+/**
+ * Compute the width of an UTF-8 string.
+ *
+ * \param s The string.
+ * \param result The width of \a s is returned here.
+ *
+ * If not in UTF8-mode. this function is just a wrapper for strlen(3).
+ * Otherwise \a s is treated as an UTF-8 string and its display width is
+ * computed. Note that this function may fail if the underlying call to
+ * mbsrtowcs(3) fails, so the caller must check the return value.
+ *
+ * \sa nl_langinfo(3), wcswidth(3).
+ *
+ * \return Standard.
+ */
+__must_check int strwidth(const char *s, size_t *result)
+{
+ const char *src = s;
+ mbstate_t state;
+ static wchar_t *dest;
+ size_t num_wchars;
+
+ /*
+ * Never call any log function here. This may result in an endless loop
+ * as para_gui's para_log() calls this function.
+ */
+
+ if (!utf8_mode()) {
+ *result = strlen(s);
+ return 0;
+ }
+ memset(&state, 0, sizeof(state));
+ *result = 0;
+ num_wchars = mbsrtowcs(NULL, &src, 0, &state);
+ if (num_wchars == (size_t)-1)
+ return -ERRNO_TO_PARA_ERROR(errno);
+ if (num_wchars == 0)
+ return 0;
+ dest = para_malloc(num_wchars * sizeof(*dest));
+ src = s;
+ memset(&state, 0, sizeof(state));
+ num_wchars = mbsrtowcs(dest, &src, num_wchars, &state);
+ assert(num_wchars > 0 && num_wchars != (size_t)-1);
+ *result = mutt_wcswidth(dest, num_wchars);
+ free(dest);
+ return 1;
+}
projects / paraslash.git / blobdiff