From: Denis Vlasenko Date: Sat, 9 Aug 2008 17:16:40 +0000 (-0000) Subject: optimize config_read() (by Timo Teras ) X-Git-Tag: 1_12_0~24 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=69f4f9a6f40e2825c93fad4d3adf453c9b33d9bb;p=oweals%2Fbusybox.git optimize config_read() (by Timo Teras ) function old new delta bb_get_chunk_with_continuation - 176 +176 find_pair 169 187 +18 ... process_stdin 443 433 -10 config_read 549 456 -93 bb_get_chunk_from_file 139 7 -132 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 7/7 up/down: 215/-254) Total: -39 bytes --- diff --git a/include/libbb.h b/include/libbb.h index 075fa055d..388e2f9ef 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -613,6 +613,7 @@ extern void xopen_xwrite_close(const char* file, const char *str) FAST_FUNC; extern void xprint_and_close_file(FILE *file) FAST_FUNC; extern char *bb_get_chunk_from_file(FILE *file, int *end) FAST_FUNC; +extern char *bb_get_chunk_with_continuation(FILE *file, int *end, int *lineno) FAST_FUNC; /* Reads up to (and including) TERMINATING_STRING: */ extern char *xmalloc_fgets_str(FILE *file, const char *terminating_string) FAST_FUNC; /* Chops off TERMINATING_STRING from the end: */ diff --git a/libbb/get_line_from_file.c b/libbb/get_line_from_file.c index 968d7572d..3cb46d240 100644 --- a/libbb/get_line_from_file.c +++ b/libbb/get_line_from_file.c @@ -9,18 +9,22 @@ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. */ -/* for getline() [GNUism] */ +/* for getline() [GNUism] #ifndef _GNU_SOURCE #define _GNU_SOURCE 1 #endif +*/ #include "libbb.h" /* This function reads an entire line from a text file, up to a newline * or NUL byte, inclusive. It returns a malloc'ed char * which * must be free'ed by the caller. If end is NULL '\n' isn't considered - * end of line. If end isn't NULL, length of the chunk read is stored in it. - * Return NULL if EOF/error */ -char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end) + * end of line. If end isn't NULL, length of the chunk is stored in it. + * If lineno is not NULL, *lineno is incremented for each line, + * and also trailing '\' is recognized as line continuation. + * + * Returns NULL if EOF/error. */ +char* FAST_FUNC bb_get_chunk_with_continuation(FILE *file, int *end, int *lineno) { int ch; int idx = 0; @@ -30,12 +34,20 @@ char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end) while ((ch = getc(file)) != EOF) { /* grow the line buffer as necessary */ if (idx >= linebufsz) { - linebufsz += 80; + linebufsz += 256; linebuf = xrealloc(linebuf, linebufsz); } linebuf[idx++] = (char) ch; - if (!ch || (end && ch == '\n')) + if (!ch) break; + if (end && ch == '\n') { + if (lineno == NULL) + break; + (*lineno)++; + if (idx < 2 || linebuf[idx-2] != '\\') + break; + idx -= 2; + } } if (end) *end = idx; @@ -52,6 +64,11 @@ char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end) return linebuf; } +char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end) +{ + return bb_get_chunk_with_continuation(file, end, NULL); +} + /* Get line, including trailing \n if any */ char* FAST_FUNC xmalloc_fgets(FILE *file) { @@ -72,7 +89,6 @@ char* FAST_FUNC xmalloc_fgetline(FILE *file) } #if 0 - /* GNUism getline() should be faster (not tested) than a loop with fgetc */ /* Get line, including trailing \n if any */ diff --git a/libbb/parse_config.c b/libbb/parse_config.c index ace6f3ad3..a0599d4b4 100644 --- a/libbb/parse_config.c +++ b/libbb/parse_config.c @@ -123,137 +123,96 @@ mintokens > 0 make config_read() print error message if less than mintokens #undef config_read int FAST_FUNC config_read(parser_t *parser, char **tokens, unsigned flags, const char *delims) { - char *line, *q; - char comment; - int ii; - int ntokens; - int mintokens; + char *line; + int ntokens, mintokens; + int t, len; - comment = *delims++; ntokens = flags & 0xFF; mintokens = (flags & 0xFF00) >> 8; - again: - memset(tokens, 0, sizeof(tokens[0]) * ntokens); - if (!parser) + if (parser == NULL) return 0; + +again: + memset(tokens, 0, sizeof(tokens[0]) * ntokens); config_free_data(parser); - while (1) { -//TODO: speed up xmalloc_fgetline by internally using fgets, not fgetc - line = xmalloc_fgetline(parser->fp); - if (!line) - return 0; + /* Read one line (handling continuations with backslash) */ + line = bb_get_chunk_with_continuation(parser->fp, &len, &parser->lineno); + if (line == NULL) + return 0; + parser->line = line; - parser->lineno++; - // handle continuations. Tito's code stolen :) - while (1) { - ii = strlen(line); - if (!ii) - goto next_line; - if (line[ii - 1] != '\\') - break; - // multi-line object - line[--ii] = '\0'; -//TODO: add xmalloc_fgetline-like iface but with appending to existing str - q = xmalloc_fgetline(parser->fp); - if (!q) - break; - parser->lineno++; - line = xasprintf("%s%s", line, q); - free(q); - } - // discard comments - if (comment) { - q = strchrnul(line, comment); - *q = '\0'; - ii = q - line; - } - // skip leading and trailing delimiters - if (flags & PARSE_TRIM) { - // skip leading - int n = strspn(line, delims); - if (n) { - ii -= n; - overlapping_strcpy(line, line + n); - } - // cut trailing - if (ii) { - while (strchr(delims, line[--ii])) - continue; - line[++ii] = '\0'; - } - } - // if something still remains -> return it - if (ii) - break; + /* Strip trailing line-feed if any */ + if (len && line[len-1] == '\n') + line[len-1] = '\0'; - next_line: - // skip empty line - free(line); - } - // non-empty line found, parse and return the number of tokens + /* Skip token in the start of line? */ + if (flags & PARSE_TRIM) + line += strspn(line, delims + 1); - // store line - parser->line = line = xrealloc(line, ii + 1); - if (flags & PARSE_KEEP_COPY) { + if (line[0] == '\0' || line[0] == delims[0]) + goto again; + + if (flags & PARSE_KEEP_COPY) parser->data = xstrdup(line); - } - // split line to tokens - ntokens--; // now it's max allowed token no - // N.B. non-empty remainder is also a token, - // so if ntokens <= 1, we just return the whole line - // N.B. if PARSE_GREEDY is set the remainder of the line is stuck to the last token - ii = 0; - while (*line && ii <= ntokens) { - //bb_info_msg("L[%s]", line); - // get next token - // at last token and need greedy token -> - if ((flags & PARSE_GREEDY) && (ii == ntokens)) { - // skip possible delimiters - if (flags & PARSE_COLLAPSE) - line += strspn(line, delims); - // don't cut the line - q = line + strlen(line); + /* Tokenize the line */ + for (t = 0; *line && *line != delims[0] && t < ntokens; t++) { + /* 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 { - // vanilla token. cut the line at the first delim - q = line + strcspn(line, delims); - if (*q) // watch out: do not step past the line end! - *q++ = '\0'; + /* Combining, find comment char if any */ + line = strchrnul(line, delims[0]); + + /* Trim any extra delimiters from the end */ + if (flags & PARSE_TRIM) { + while (strchr(delims + 1, line[-1]) != NULL) + line--; + } } - // pin token - if (!(flags & (PARSE_COLLAPSE | PARSE_TRIM)) || *line) { - //bb_info_msg("N[%d] T[%s]", ii, line); - tokens[ii++] = line; - // process escapes in token -#if 0 // unused so far - if (flags & PARSE_ESCAPE) { - char *s = line; - while (*s) { - if (*s == '\\') { - s++; - *line++ = bb_process_escape_sequence((const char **)&s); - } else { - *line++ = *s++; - } + + /* Token not terminated? */ + if (line[0] == delims[0]) + *line = '\0'; + else if (line[0] != '\0') + *(line++) = '\0'; + +#if 0 /* unused so far */ + if (flags & PARSE_ESCAPE) { + const char *from; + char *to; + + from = to = tokens[t]; + while (*from) { + if (*from == '\\') { + from++; + *to++ = bb_process_escape_sequence(&from); + } else { + *to++ = *from++; } - *line = '\0'; } -#endif + *to = '\0'; } - line = q; - //bb_info_msg("A[%s]", line); +#endif + + /* Skip possible delimiters */ + if (flags & PARSE_COLLAPSE) + line += strspn(line, delims + 1); } - if (ii < mintokens) { + if (t < mintokens) { bb_error_msg("bad line %u: %d tokens found, %d needed", - parser->lineno, ii, mintokens); + parser->lineno, t, mintokens); if (flags & PARSE_MIN_DIE) xfunc_die(); - ntokens++; goto again; } - return ii; + return t; }