1 /* $NetBSD: searchpath.cpp,v 1.1.1.1 2016/01/13 18:41:48 christos Exp $ */
2
3 // -*- C++ -*-
4 /* Copyright (C) 1989, 1990, 1991, 1992, 2000, 2001, 2003, 2005
5 Free Software Foundation, Inc.
6 Written by James Clark (jjc@jclark.com)
7
8 This file is part of groff.
9
10 groff is free software; you can redistribute it and/or modify it under
11 the terms of the GNU General Public License as published by the Free
12 Software Foundation; either version 2, or (at your option) any later
13 version.
14
15 groff is distributed in the hope that it will be useful, but WITHOUT ANY
16 WARRANTY; without even the implied warranty of MERCHANTABILITY or
17 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 for more details.
19
20 You should have received a copy of the GNU General Public License along
21 with groff; see the file COPYING. If not, write to the Free Software
22 Foundation, 51 Franklin St - Fifth Floor, Boston, MA 02110-1301, USA. */
23
24 #include "lib.h"
25
26 #include <stdlib.h>
27 #include <assert.h>
28 #include <errno.h>
29
30 #include "searchpath.h"
31 #include "nonposix.h"
32
33 #ifdef _WIN32
34 # include "relocate.h"
35 #else
36 # define relocate(path) strsave(path)
37 #endif
38
search_path(const char * envvar,const char * standard,int add_home,int add_current)39 search_path::search_path(const char *envvar, const char *standard,
40 int add_home, int add_current)
41 {
42 char *home = 0;
43 if (add_home)
44 home = getenv("HOME");
45 char *e = 0;
46 if (envvar)
47 e = getenv(envvar);
48 dirs = new char[((e && *e) ? strlen(e) + 1 : 0)
49 + (add_current ? 1 + 1 : 0)
50 + ((home && *home) ? strlen(home) + 1 : 0)
51 + ((standard && *standard) ? strlen(standard) : 0)
52 + 1];
53 *dirs = '\0';
54 if (e && *e) {
55 strcat(dirs, e);
56 strcat(dirs, PATH_SEP);
57 }
58 if (add_current) {
59 strcat(dirs, ".");
60 strcat(dirs, PATH_SEP);
61 }
62 if (home && *home) {
63 strcat(dirs, home);
64 strcat(dirs, PATH_SEP);
65 }
66 if (standard && *standard)
67 strcat(dirs, standard);
68 init_len = strlen(dirs);
69 }
70
~search_path()71 search_path::~search_path()
72 {
73 // dirs is always allocated
74 a_delete dirs;
75 }
76
command_line_dir(const char * s)77 void search_path::command_line_dir(const char *s)
78 {
79 char *old = dirs;
80 unsigned old_len = strlen(old);
81 unsigned slen = strlen(s);
82 dirs = new char[old_len + 1 + slen + 1];
83 memcpy(dirs, old, old_len - init_len);
84 char *p = dirs;
85 p += old_len - init_len;
86 if (init_len == 0)
87 *p++ = PATH_SEP_CHAR;
88 memcpy(p, s, slen);
89 p += slen;
90 if (init_len > 0) {
91 *p++ = PATH_SEP_CHAR;
92 memcpy(p, old + old_len - init_len, init_len);
93 p += init_len;
94 }
95 *p++ = '\0';
96 a_delete old;
97 }
98
open_file(const char * name,char ** pathp)99 FILE *search_path::open_file(const char *name, char **pathp)
100 {
101 assert(name != 0);
102 if (IS_ABSOLUTE(name) || *dirs == '\0') {
103 FILE *fp = fopen(name, "r");
104 if (fp) {
105 if (pathp)
106 *pathp = strsave(name);
107 return fp;
108 }
109 else
110 return 0;
111 }
112 unsigned namelen = strlen(name);
113 char *p = dirs;
114 for (;;) {
115 char *end = strchr(p, PATH_SEP_CHAR);
116 if (!end)
117 end = strchr(p, '\0');
118 int need_slash = end > p && strchr(DIR_SEPS, end[-1]) == 0;
119 char *origpath = new char[(end - p) + need_slash + namelen + 1];
120 memcpy(origpath, p, end - p);
121 if (need_slash)
122 origpath[end - p] = '/';
123 strcpy(origpath + (end - p) + need_slash, name);
124 #if 0
125 fprintf(stderr, "origpath `%s'\n", origpath);
126 #endif
127 char *path = relocate(origpath);
128 a_delete origpath;
129 #if 0
130 fprintf(stderr, "trying `%s'\n", path);
131 #endif
132 FILE *fp = fopen(path, "r");
133 if (fp) {
134 if (pathp)
135 *pathp = path;
136 else
137 a_delete path;
138 return fp;
139 }
140 a_delete path;
141 if (*end == '\0')
142 break;
143 p = end + 1;
144 }
145 return 0;
146 }
147
open_file_cautious(const char * name,char ** pathp,const char * mode)148 FILE *search_path::open_file_cautious(const char *name, char **pathp,
149 const char *mode)
150 {
151 if (!mode)
152 mode = "r";
153 bool reading = (strchr(mode, 'r') != 0);
154 if (name == 0 || strcmp(name, "-") == 0) {
155 if (pathp)
156 *pathp = strsave(reading ? "stdin" : "stdout");
157 return (reading ? stdin : stdout);
158 }
159 if (!reading || IS_ABSOLUTE(name) || *dirs == '\0') {
160 FILE *fp = fopen(name, mode);
161 if (fp) {
162 if (pathp)
163 *pathp = strsave(name);
164 return fp;
165 }
166 else
167 return 0;
168 }
169 unsigned namelen = strlen(name);
170 char *p = dirs;
171 for (;;) {
172 char *end = strchr(p, PATH_SEP_CHAR);
173 if (!end)
174 end = strchr(p, '\0');
175 int need_slash = end > p && strchr(DIR_SEPS, end[-1]) == 0;
176 char *origpath = new char[(end - p) + need_slash + namelen + 1];
177 memcpy(origpath, p, end - p);
178 if (need_slash)
179 origpath[end - p] = '/';
180 strcpy(origpath + (end - p) + need_slash, name);
181 #if 0
182 fprintf(stderr, "origpath `%s'\n", origpath);
183 #endif
184 char *path = relocate(origpath);
185 a_delete origpath;
186 #if 0
187 fprintf(stderr, "trying `%s'\n", path);
188 #endif
189 FILE *fp = fopen(path, mode);
190 if (fp) {
191 if (pathp)
192 *pathp = path;
193 else
194 a_delete path;
195 return fp;
196 }
197 int err = errno;
198 a_delete path;
199 if (err != ENOENT)
200 {
201 errno = err;
202 return 0;
203 }
204 if (*end == '\0')
205 break;
206 p = end + 1;
207 }
208 errno = ENOENT;
209 return 0;
210 }
211