1 /*
2 * argv_parse.c --- utility function for parsing a string into a
3 * argc, argv array.
4 *
5 * This file defines a function argv_parse() which parsing a
6 * passed-in string, handling double quotes and backslashes, and
7 * creates an allocated argv vector which can be freed using the
8 * argv_free() function.
9 *
10 * See argv_parse.h for the formal definition of the functions.
11 *
12 * Copyright 1999 by Theodore Ts'o.
13 *
14 * Permission to use, copy, modify, and distribute this software for
15 * any purpose with or without fee is hereby granted, provided that
16 * the above copyright notice and this permission notice appear in all
17 * copies. THE SOFTWARE IS PROVIDED "AS IS" AND THEODORE TS'O (THE
18 * AUTHOR) DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
19 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
21 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
22 * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
23 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
24 * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. (Isn't
25 * it sick that the U.S. culture of lawsuit-happy lawyers requires
26 * this kind of disclaimer?)
27 *
28 * Version 1.1, modified 2/27/1999
29 */
30
31 #include "config.h"
32 #ifdef HAVE_STDLIB_H
33 #include <stdlib.h>
34 #endif
35 #include <ctype.h>
36 #include <string.h>
37 #include "argv_parse.h"
38
39 #define STATE_WHITESPACE 1
40 #define STATE_TOKEN 2
41 #define STATE_QUOTED 3
42
43 /*
44 * Returns 0 on success, -1 on failure.
45 */
argv_parse(char * in_buf,int * ret_argc,char *** ret_argv)46 int argv_parse(char *in_buf, int *ret_argc, char ***ret_argv)
47 {
48 int argc = 0, max_argc = 0;
49 char **argv, **new_argv, *buf, ch;
50 char *cp = 0, *outcp = 0;
51 int state = STATE_WHITESPACE;
52
53 buf = malloc(strlen(in_buf)+1);
54 if (!buf)
55 return -1;
56
57 max_argc = 0; argc = 0; argv = 0;
58 outcp = buf;
59 for (cp = in_buf; (ch = *cp); cp++) {
60 if (state == STATE_WHITESPACE) {
61 if (isspace((int) ch))
62 continue;
63 /* Not whitespace, so start a new token */
64 state = STATE_TOKEN;
65 if (argc >= max_argc) {
66 max_argc += 3;
67 new_argv = realloc(argv,
68 (max_argc+1)*sizeof(char *));
69 if (!new_argv) {
70 free(argv);
71 free(buf);
72 return -1;
73 }
74 argv = new_argv;
75 }
76 argv[argc++] = outcp;
77 }
78 if (state == STATE_QUOTED) {
79 if (ch == '"')
80 state = STATE_TOKEN;
81 else
82 *outcp++ = ch;
83 continue;
84 }
85 /* Must be processing characters in a word */
86 if (isspace((int) ch)) {
87 /*
88 * Terminate the current word and start
89 * looking for the beginning of the next word.
90 */
91 *outcp++ = 0;
92 state = STATE_WHITESPACE;
93 continue;
94 }
95 if (ch == '"') {
96 state = STATE_QUOTED;
97 continue;
98 }
99 if (ch == '\\') {
100 ch = *++cp;
101 switch (ch) {
102 case '\0':
103 ch = '\\'; cp--; break;
104 case 'n':
105 ch = '\n'; break;
106 case 't':
107 ch = '\t'; break;
108 case 'b':
109 ch = '\b'; break;
110 }
111 }
112 *outcp++ = ch;
113 }
114 if (state != STATE_WHITESPACE)
115 *outcp++ = '\0';
116 if (argv == 0) {
117 argv = malloc(sizeof(char *));
118 free(buf);
119 }
120 argv[argc] = 0;
121 if (ret_argc)
122 *ret_argc = argc;
123 if (ret_argv)
124 *ret_argv = argv;
125 return 0;
126 }
127
argv_free(char ** argv)128 void argv_free(char **argv)
129 {
130 free(*argv);
131 free(argv);
132 }
133
134 #ifdef DEBUG
135 /*
136 * For debugging
137 */
138
139 #include <stdio.h>
140
main(int argc,char ** argv)141 int main(int argc, char **argv)
142 {
143 int ac, ret;
144 char **av, **cpp;
145 char buf[256];
146
147 while (!feof(stdin)) {
148 if (fgets(buf, sizeof(buf), stdin) == NULL)
149 break;
150 ret = argv_parse(buf, &ac, &av);
151 if (ret != 0) {
152 printf("Argv_parse returned %d!\n", ret);
153 continue;
154 }
155 printf("Argv_parse returned %d arguments...\n", ac);
156 for (cpp = av; *cpp; cpp++) {
157 if (cpp != av)
158 printf(", ");
159 printf("'%s'", *cpp);
160 }
161 printf("\n");
162 argv_free(av);
163 }
164 exit(0);
165 }
166 #endif /* DEBUG */
167