+
+/**
+ * Split a 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 occurance 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.
+ */
+__must_check unsigned split_args(char *args, char *** const argv_ptr, const char *delim)
+{
+ char *p = args;
+ 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 = adu_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;
+}
+
+
+static int get_next_word(const char *line, char **word)
+{
+ enum line_state_flags {LSF_HAVE_WORD = 1, LSF_BACKSLASH = 2,
+ LSF_QUOTE = 4};
+ const char *in;
+ char *out;
+ int ret, state = 0;
+
+ out = adu_malloc(strlen(line) + 1);
+ *out = '\0';
+ *word = out;
+ for (in = line; *in; in++) {
+ switch (*in) {
+ case '\\':
+ if (state & LSF_BACKSLASH) /* \\ */
+ break;
+ 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;
+ }
+ break;
+ case '"':
+ if (state & LSF_BACKSLASH) /* \" */
+ break;
+ if (state & LSF_QUOTE) {
+ state &= ~LSF_QUOTE;
+ continue;
+ }
+ state |= LSF_HAVE_WORD;
+ state |= LSF_QUOTE;
+ continue;
+ case ' ':
+ case '\t':
+ case '\n':
+ if (state & LSF_BACKSLASH)
+ break;
+ if (state & LSF_QUOTE)
+ break;
+ if (state & LSF_HAVE_WORD)
+ goto success;
+ /* ignore space 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_ERROR(EINVAL);
+ if (state & LSF_BACKSLASH) {
+ ERROR_LOG("trailing backslash\n");
+ goto out;
+ }
+ if (state & LSF_QUOTE) {
+ ERROR_LOG("unmatched quote character\n");
+ goto out;
+ }
+success:
+ *out = '\0';
+ return in - line;
+out:
+ free(*word);
+ *word = NULL;
+ return ret;
+}
+
+/**
+ * Free an array of words created by create_argv().
+ *
+ * \param argv A pointer previously obtained by \ref create_argv().
+ */
+void free_argv(char **argv)
+{
+ int i;
+
+ for (i = 0; argv[i]; i++)
+ free(argv[i]);
+ free(argv);
+}
+
+/**
+ * Split a line into words which are separated by whitespace.
+ *
+ * In contrast to gengetopt's string parser, double quotes, backslash-escaped
+ * characters and special characters like \p \\n are honored. The result
+ * contains pointers to copies of the words contained in \a line and has to be
+ * freed by using \ref free_argv().
+ *
+ * \param line The line to be split.
+ * \param result The array of words is returned here.
+ *
+ * \return Number of words in \a line, negative on errors.
+ */
+int create_argv(const char *line, char ***result)
+{
+ char *word, **argv = adu_malloc(2 * sizeof(char *));
+ const char *p;
+ int ret, num_words;
+
+ argv[0] = adu_strdup(line);
+ for (p = line, num_words = 1; ; p += ret, num_words++) {
+ ret = get_next_word(p, &word);
+ if (ret < 0)
+ goto err;
+ if (!ret)
+ break;
+ argv = adu_realloc(argv, (num_words + 2) * sizeof(char*));
+ argv[num_words] = word;
+ }
+ argv[num_words] = NULL;
+ *result = argv;
+ return num_words;
+err:
+ while (num_words > 0)
+ free(argv[--num_words]);
+ free(argv);
+ return ret;
+}