*
* Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>
*
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ * Also for use in uClibc (http://uclibc.org/) licensed under LGPLv2.1 or later.
*/
-#include "libbb.h"
+/* Uncomment to enable test applet */
+////config:config PARSE
+////config: bool "Uniform config file parser debugging applet: parse"
+////config: default n
+////config: help
+////config: Typical usage of parse API:
+////config: char *t[3];
+////config: parser_t *p = config_open(filename);
+////config: while (config_read(p, t, 3, 0, delimiters, flags)) { // 1..3 tokens
+////config: bb_error_msg("TOKENS: '%s''%s''%s'", t[0], t[1], t[2]);
+////config: }
+////config: config_close(p);
-/*
+////applet:IF_PARSE(APPLET(parse, BB_DIR_USR_BIN, BB_SUID_DROP))
-Typical usage:
-
------ CUT -----
- char *t[3]; // tokens placeholder
- parser_t p; // parser structure
- // open file
- if (config_open(filename, &p)) {
- // parse line-by-line
- while (*config_read(&p, t, 3, 0, delimiters, comment_char) >= 0) { // 0..3 tokens
- // use tokens
- bb_error_msg("TOKENS: [%s][%s][%s]", t[0], t[1], t[2]);
- }
- ...
- // free parser
- config_close(&p);
- }
------ CUT -----
+//kbuild:lib-y += parse_config.o
-*/
+//usage:#define parse_trivial_usage
+//usage: "[-x] [-n MAXTOKENS] [-m MINTOKENS] [-d DELIMS] [-f FLAGS] FILE..."
+//usage:#define parse_full_usage "\n\n"
+//usage: " -x Suppress output (for benchmarking)"
+
+#include "libbb.h"
-FILE* FAST_FUNC config_open(parser_t *parser, const char *filename)
+#if defined ENABLE_PARSE && ENABLE_PARSE
+int parse_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int parse_main(int argc UNUSED_PARAM, char **argv)
{
- // empty file configures nothing!
- parser->fp = fopen_or_warn(filename, "r");
- if (!parser->fp)
- return parser->fp;
+ const char *delims = "# \t";
+ char **t;
+ unsigned flags = PARSE_NORMAL;
+ int mintokens = 0, ntokens = 128;
+ unsigned noout;
+
+ opt_complementary = "-1:n+:m+:f+";
+ noout = 1 & getopt32(argv, "xn:m:d:f:", &ntokens, &mintokens, &delims, &flags);
+ //argc -= optind;
+ argv += optind;
+
+ t = xmalloc(sizeof(t[0]) * ntokens);
+ while (*argv) {
+ int n;
+ parser_t *p = config_open(*argv);
+ while ((n = config_read(p, t, ntokens, mintokens, delims, flags)) != 0) {
+ if (!noout) {
+ for (int i = 0; i < n; ++i)
+ printf("[%s]", t[i]);
+ puts("");
+ }
+ }
+ config_close(p);
+ argv++;
+ }
+ return EXIT_SUCCESS;
+}
+#endif
- // init parser
- parser->line = NULL;
- parser->lineno = 0;
+parser_t* FAST_FUNC config_open2(const char *filename, FILE* FAST_FUNC (*fopen_func)(const char *path))
+{
+ FILE* fp;
+ parser_t *parser;
+
+ fp = fopen_func(filename);
+ if (!fp)
+ return NULL;
+ parser = xzalloc(sizeof(*parser));
+ parser->fp = fp;
+ return parser;
+}
- return parser->fp;
+parser_t* FAST_FUNC config_open(const char *filename)
+{
+ return config_open2(filename, fopen_or_warn_stdin);
}
void FAST_FUNC config_close(parser_t *parser)
{
- free(parser->line);
- free(parser->data);
- fclose(parser->fp);
+ if (parser) {
+ if (PARSE_KEEP_COPY) /* compile-time constant */
+ free(parser->data);
+ fclose(parser->fp);
+ free(parser->line);
+ free(parser->nline);
+ free(parser);
+ }
}
-int FAST_FUNC config_read(parser_t *parser, char **tokens, int ntokens, int mintokens, const char *delims, char comment)
+/* This function reads an entire line from a text file,
+ * up to a newline, exclusive.
+ * Trailing '\' is recognized as line continuation.
+ * Returns -1 if EOF/error.
+ */
+static int get_line_with_continuation(parser_t *parser)
{
- char *line, *q;
- int token_num, len;
- int noreduce = (ntokens < 0); // do not treat subsequent delimiters as one delimiter
-
- if (ntokens < 0)
- ntokens = -ntokens;
+ ssize_t len, nlen;
+ char *line;
- // nullify tokens
- memset(tokens, 0, sizeof(void *) * ntokens);
+ len = getline(&parser->line, &parser->line_alloc, parser->fp);
+ if (len <= 0)
+ return len;
- // free used line
- free(parser->line);
- parser->line = NULL;
- free(parser->data);
- parser->data = NULL;
-
- while (1) {
- int n;
+ line = parser->line;
+ for (;;) {
+ parser->lineno++;
+ if (line[len - 1] == '\n')
+ len--;
+ if (len == 0 || line[len - 1] != '\\')
+ break;
+ len--;
- // get fresh line
-//TODO: speed up xmalloc_fgetline by internally using fgets, not fgetc
- line = xmalloc_fgetline(parser->fp);
- if (!line)
- return -1;
+ nlen = getline(&parser->nline, &parser->nline_alloc, parser->fp);
+ if (nlen <= 0)
+ break;
- parser->lineno++;
- // handle continuations. Tito's code stolen :)
- while (1) {
- len = strlen(line);
- if (!len)
- goto free_and_cont;
- if (line[len - 1] != '\\')
- break;
- // multi-line object
- line[--len] = '\0';
-//TODO: add xmalloc_fgetline-like iface but with appending to existing str
- q = xmalloc_fgetline(parser->fp);
- if (q) {
- parser->lineno++;
- line = xasprintf("%s%s", line, q);
- free(q);
- }
- }
- // comments mean EOLs
- if (comment) {
- q = strchrnul(line, comment);
- *q = '\0';
- len = q - line;
- }
- // skip leading delimiters
- n = strspn(line, delims);
- if (n) {
- len -= n;
- strcpy(line, line + n);
+ if (parser->line_alloc < len + nlen + 1) {
+ parser->line_alloc = len + nlen + 1;
+ line = parser->line = xrealloc(line, parser->line_alloc);
}
- if (len)
- break;
- // skip empty lines
- free_and_cont:
- free(line);
+ memcpy(&line[len], parser->nline, nlen);
+ len += nlen;
}
- // non-empty line found, parse and return
+ line[len] = '\0';
+ return len;
+}
- // store line
- parser->line = line = xrealloc(line, len + 1);
- parser->data = xstrdup(line);
- // now split line to tokens
-//TODO: discard consecutive delimiters?
- token_num = 0;
- ntokens--; // now it's max allowed token no
- while (1) {
- // get next token
- if (token_num == ntokens)
- break;
- q = line + strcspn(line, delims);
- if (!*q)
- break;
- // pin token
- *q++ = '\0';
- if (noreduce || *line) {
- tokens[token_num++] = line;
-//bb_error_msg("L[%d] T[%s]", token_num, line);
+/*
+0. If parser is NULL return 0.
+1. Read a line from config file. If nothing to read then return 0.
+ Handle continuation character. Advance lineno for each physical line.
+ Discard everything past comment character.
+2. if PARSE_TRIM is set (default), remove leading and trailing delimiters.
+3. If resulting line is empty goto 1.
+4. Look for first delimiter. If !PARSE_COLLAPSE or !PARSE_TRIM is set then
+ remember the token as empty.
+5. Else (default) if number of seen tokens is equal to max number of tokens
+ (token is the last one) and PARSE_GREEDY is set then the remainder
+ of the line is the last token.
+ Else (token is not last or PARSE_GREEDY is not set) just replace
+ first delimiter with '\0' thus delimiting the token.
+6. Advance line pointer past the end of token. If number of seen tokens
+ is less than required number of tokens then goto 4.
+7. Check the number of seen tokens is not less the min number of tokens.
+ Complain or die otherwise depending on PARSE_MIN_DIE.
+8. Return the number of seen tokens.
+
+mintokens > 0 make config_read() print error message if less than mintokens
+(but more than 0) are found. Empty lines are always skipped (not warned about).
+*/
+#undef config_read
+int FAST_FUNC config_read(parser_t *parser, char **tokens, unsigned flags, const char *delims)
+{
+ char *line;
+ int ntokens, mintokens;
+ int t;
+
+ if (!parser)
+ return 0;
+
+ ntokens = (uint8_t)flags;
+ mintokens = (uint8_t)(flags >> 8);
+
+ again:
+ memset(tokens, 0, sizeof(tokens[0]) * ntokens);
+
+ /* Read one line (handling continuations with backslash) */
+ if (get_line_with_continuation(parser) < 0)
+ return 0;
+
+ line = parser->line;
+
+ /* Skip token in the start of line? */
+ if (flags & PARSE_TRIM)
+ line += strspn(line, delims + 1);
+
+ if (line[0] == '\0' || line[0] == delims[0])
+ goto again;
+
+ if (flags & PARSE_KEEP_COPY) {
+ free(parser->data);
+ parser->data = xstrdup(line);
+ }
+
+ /* Tokenize the line */
+ t = 0;
+ do {
+ /* Pin token */
+ tokens[t] = line;
+
+ /* Combine remaining arguments? */
+ if ((t != (ntokens-1)) || !(flags & PARSE_GREEDY)) {
+ /* Vanilla token, find next delimiter */
+ line += strcspn(line, delims[0] ? delims : delims + 1);
+ } else {
+ /* Combining, find comment char if any */
+ line = strchrnul(line, PARSE_EOL_COMMENTS ? delims[0] : '\0');
+
+ /* Trim any extra delimiters from the end */
+ if (flags & PARSE_TRIM) {
+ while (strchr(delims + 1, line[-1]) != NULL)
+ line--;
+ }
}
- line = q;
- }
- // non-empty remainder is also a token,
- // so if ntokens <= 1, we just return the whole line
- if (noreduce || *line)
- tokens[token_num++] = line;
+ /* Token not terminated? */
+ if (*line == delims[0])
+ *line = '\0';
+ else if (*line != '\0')
+ *line++ = '\0';
- if (token_num < mintokens)
- bb_error_msg_and_die("bad line %u: %d tokens found, %d needed",
- parser->lineno, token_num, mintokens);
+#if 0 /* unused so far */
+ if (flags & PARSE_ESCAPE) {
+ strcpy_and_process_escape_sequences(tokens[t], tokens[t]);
+ }
+#endif
+ /* Skip possible delimiters */
+ if (flags & PARSE_COLLAPSE)
+ line += strspn(line, delims + 1);
+
+ t++;
+ } while (*line && *line != delims[0] && t < ntokens);
+
+ if (t < mintokens) {
+ bb_error_msg("bad line %u: %d tokens found, %d needed",
+ parser->lineno, t, mintokens);
+ if (flags & PARSE_MIN_DIE)
+ xfunc_die();
+ goto again;
+ }
- return token_num;
+ return t;
}