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
168
169
170
171
172
|
/* Routines for dealing with '\0' separated environment vectors
Copyright (C) 1995-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Written by Miles Bader <miles@gnu.org>
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <malloc.h>
#include <string.h>
#include <envz.h>
/* The character separating names from values in an envz. */
#define SEP '='
/* Returns a pointer to the entry in ENVZ for NAME, or 0 if there is none.
If NAME contains the separator character, only the portion before it is
used in the comparison. */
char *
envz_entry (const char *envz, size_t envz_len, const char *name)
{
while (envz_len)
{
const char *p = name;
const char *entry = envz; /* Start of this entry. */
/* See how far NAME and ENTRY match. */
while (envz_len && *p == *envz && *p && *p != SEP)
p++, envz++, envz_len--;
if ((*envz == '\0' || *envz == SEP) && (*p == '\0' || *p == SEP))
/* Bingo! */
return (char *) entry;
/* No match, skip to the next entry. */
while (envz_len && *envz)
envz++, envz_len--;
if (envz_len)
envz++, envz_len--; /* skip '\0' */
}
return 0;
}
libc_hidden_def (envz_entry)
/* Returns a pointer to the value portion of the entry in ENVZ for NAME, or 0
if there is none. */
char *
envz_get (const char *envz, size_t envz_len, const char *name)
{
char *entry = envz_entry (envz, envz_len, name);
if (entry)
{
while (*entry && *entry != SEP)
entry++;
if (*entry)
entry++;
else
entry = 0; /* A null entry. */
}
return entry;
}
/* Remove the entry for NAME from ENVZ & ENVZ_LEN, if any. */
void
envz_remove (char **envz, size_t *envz_len, const char *name)
{
char *entry = envz_entry (*envz, *envz_len, name);
if (entry)
argz_delete (envz, envz_len, entry);
}
libc_hidden_def (envz_remove)
/* Adds an entry for NAME with value VALUE to ENVZ & ENVZ_LEN. If an entry
with the same name already exists in ENVZ, it is removed. If VALUE is
NULL, then the new entry will a special null one, for which envz_get will
return NULL, although envz_entry will still return an entry; this is handy
because when merging with another envz, the null entry can override an
entry in the other one. Null entries can be removed with envz_strip (). */
error_t
envz_add (char **envz, size_t *envz_len, const char *name, const char *value)
{
envz_remove (envz, envz_len, name);
if (value)
/* Add the new value, if there is one. */
{
size_t name_len = strlen (name);
size_t value_len = strlen (value);
size_t old_envz_len = *envz_len;
size_t new_envz_len = old_envz_len + name_len + 1 + value_len + 1;
char *new_envz = realloc (*envz, new_envz_len);
if (new_envz)
{
memcpy (new_envz + old_envz_len, name, name_len);
new_envz[old_envz_len + name_len] = SEP;
memcpy (new_envz + old_envz_len + name_len + 1, value, value_len);
new_envz[new_envz_len - 1] = 0;
*envz = new_envz;
*envz_len = new_envz_len;
return 0;
}
else
return ENOMEM;
}
else
/* Add a null entry. */
return __argz_add (envz, envz_len, name);
}
/* Adds each entry in ENVZ2 to ENVZ & ENVZ_LEN, as if with envz_add(). If
OVERRIDE is true, then values in ENVZ2 will supersede those with the same
name in ENV, otherwise not. */
error_t
envz_merge (char **envz, size_t *envz_len, const char *envz2,
size_t envz2_len, int override)
{
error_t err = 0;
while (envz2_len && ! err)
{
char *old = envz_entry (*envz, *envz_len, envz2);
size_t new_len = strlen (envz2) + 1;
if (! old)
err = __argz_append (envz, envz_len, envz2, new_len);
else if (override)
{
argz_delete (envz, envz_len, old);
err = __argz_append (envz, envz_len, envz2, new_len);
}
envz2 += new_len;
envz2_len -= new_len;
}
return err;
}
/* Remove null entries. */
void
envz_strip (char **envz, size_t *envz_len)
{
char *entry = *envz;
size_t left = *envz_len;
while (left)
{
size_t entry_len = strlen (entry) + 1;
left -= entry_len;
if (! strchr (entry, SEP))
/* Null entry. */
memmove (entry, entry + entry_len, left);
else
entry += entry_len;
}
*envz_len = entry - *envz;
}
|
