1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
|
/* Part of publib.
Copyright (c) 1994-2006 Lars Wirzenius. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following
disclaimer in the documentation and/or other materials provided
with the distribution.
THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* strvars.c -- expand variables in string
*
* Part of publib. See man page for more information.
* "@(#)publib-strutil:$Id: strvars.c,v 1.6 1995/08/24 16:51:36 liw Exp $"
*/
#include <assert.h>
#include <string.h>
#include <stdlib.h>
#include "publib/strutil.h"
#include "publib/errormsg.h"
/*
* Add `s' to end of `*r', allocating more memory.
*/
static int add_to_end(char **r, size_t *size, const char *str, size_t n) {
char *p;
p = realloc(*r, *size + n);
if (p == NULL) {
__publib_error("realloc failed");
return -1;
}
*r = p;
memcpy(*r + *size, str, n);
*size += n;
return 0;
}
/*
* Copy to next '$' or end of string (including '\0'). Return -1 for
* error (out of memory), or 0 for '$' not found, or 1 for '$' found.
* Advance *str appropriately.
*/
static int copy_to_dollar(char **r, size_t *size, const char **str) {
size_t n;
int ret;
n = strcspn(*str, "$");
assert((*str)[n] == '\0' || (*str)[n] == '$');
if ((*str)[n] == '\0') {
++n;
ret = 0;
} else
ret = 1;
if (n > 0) {
if (add_to_end(r, size, *str, n) == -1)
return -1;
*str += n;
}
return ret;
}
/*
* Get value of a variable. Return NULL for failure, otherwise value.
*/
static char *value_of(const char **str, char *(*expand)(const char *)) {
char *value;
assert(str != NULL);
assert(*str != NULL);
assert(**str == '$');
if ((*str)[1] == '\0') {
value = "$";
*str += 2;
} else if ((*str)[1] == '(') {
char *name;
size_t n = strcspn(*str+2, ")");
if ((*str)[n] == '\0') {
__publib_error("syntax error for variable reference");
return NULL;
}
*str += 2;
name = strndup(*str, n);
if (name == NULL) {
__publib_error("strdup failed");
return NULL;
}
value = expand(name);
free(name);
if (value == NULL) {
__publib_error("unknown variable name");
return NULL;
}
*str += n;
} else {
char onechar[] = "x";
onechar[0] = (*str)[1];
value = expand(onechar);
if (value == NULL) {
__publib_error("unknown variable name");
return NULL;
}
*str += 2;
}
return value;
}
int strvars(char **res, const char *str, char *(*expand)(const char *)) {
char *r, *value;
size_t size;
int ret;
assert(res != NULL);
assert(str != NULL);
assert(expand != NULL);
r = NULL;
size = 0;
for (;;) {
ret = copy_to_dollar(&r, &size, &str);
if (ret == -1)
return -1;
else if (ret == 0)
break;
value = value_of(&str, expand);
if (value == NULL)
return -1;
if (add_to_end(&r, &size, value, strlen(value) + 1) == -1)
return -1;
}
*res = r;
return 0;
}
|
