s3-lib: add srprs, primitives to build simple recursive parsers
[Samba.git] / source3 / lib / srprs.c
blob77464f5f3adebddf04ab58b30f1c076d5624beb0
1 /*
2 * Samba Unix/Linux SMB client library
4 * Copyright (C) Gregor Beck 2010
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
20 /**
21 * @file srprs.c
22 * @author Gregor Beck <gb@sernet.de>
23 * @date Aug 2010
24 * @brief A simple recursive parser.
27 #include "srprs.h"
28 #include "cbuf.h"
29 #include <ctype.h>
30 #include <string.h>
31 #include <assert.h>
32 #include <stdio.h>
34 bool srprs_skipws(const char** ptr) {
35 while (isspace(**ptr))
36 ++(*ptr);
37 return true;
40 bool srprs_char(const char** ptr, char c) {
41 if (**ptr == c) {
42 ++(*ptr);
43 return true;
45 return false;
48 bool srprs_str(const char** ptr, const char* str, size_t len)
50 if (len == -1)
51 len = strlen(str);
53 if (memcmp(*ptr, str, len) == 0) {
54 *ptr += len;
55 return true;
57 return false;
60 bool srprs_charset(const char** ptr, const char* set, cbuf* oss)
62 const char* p = strchr(set, **ptr);
63 if (p != NULL && *p != '\0') {
64 cbuf_putc(oss, **ptr);
65 ++(*ptr);
66 return true;
68 return false;
71 bool srprs_charsetinv(const char** ptr, const char* set, cbuf* oss)
73 if ((**ptr != '\0') && (strchr(set, **ptr) == NULL)) {
74 cbuf_putc(oss, **ptr);
75 ++(*ptr);
76 return true;
78 return false;
83 bool srprs_quoted_string(const char** ptr, cbuf* str, bool* cont)
85 const char* pos = *ptr;
86 const size_t spos = cbuf_getpos(str);
88 if (cont == NULL || *cont == false) {
89 if (!srprs_char(&pos, '\"'))
90 goto fail;
93 while (true) {
94 while (srprs_charsetinv(&pos, "\\\"", str))
97 switch (*pos) {
98 case '\0':
99 if (cont == NULL) {
100 goto fail;
101 } else {
102 *ptr = pos;
103 *cont = true;
104 return true;
106 case '\"':
107 *ptr = pos+1;
108 if (cont != NULL) {
109 *cont = false;
111 return true;
113 case '\\':
114 pos++;
115 if (!srprs_charset(&pos, "\\\"", str))
116 goto fail;
117 break;
119 default:
120 assert(false);
124 fail:
125 cbuf_setpos(str, spos);
126 return false;
129 bool srprs_hex(const char** ptr, size_t len, unsigned* u)
131 static const char* FMT[] = {
132 "%1x","%2x","%3x","%4x","%5x","%6x","%7x","%8x",
133 "%9x","%10x","%11x","%12x","%13x","%14x","%15x","%16x"
136 const char* pos = *ptr;
137 int ret;
138 int i;
140 assert((len > 0)
141 && (len <= 2*sizeof(unsigned))
142 && (len <= sizeof(FMT)/sizeof(const char*)));
144 for (i=0; i<len; i++) {
145 if (!srprs_charset(&pos, "0123456789abcdefABCDEF", NULL)) {
146 break;
150 ret = sscanf(*ptr, FMT[len-1], u);
152 if ( ret != 1 ) {
153 return false;
156 *ptr = pos;
157 return true;
160 bool srprs_nl(const char** ptr, cbuf* nl)
162 static const char CRLF[] = "\r\n";
163 if (srprs_str(ptr, CRLF, sizeof(CRLF) - 1)) {
164 cbuf_puts(nl, CRLF, sizeof(CRLF) - 1);
165 return true;
167 return srprs_charset(ptr, "\n\r", nl);
170 bool srprs_eos(const char** ptr)
172 return (**ptr == '\0');
175 bool srprs_eol(const char** ptr, cbuf* nl)
177 return srprs_eos(ptr) || srprs_nl(ptr, nl);
180 bool srprs_line(const char** ptr, cbuf* str)
182 while (srprs_charsetinv(ptr, "\n\r", str))
184 return true;