freebsd-src/contrib/groff/libgroff/searchpath.cc
1996-09-07 16:18:32 +00:00

118 lines
2.8 KiB
C++

// -*- C++ -*-
/* Copyright (C) 1989, 1990, 1991, 1992 Free Software Foundation, Inc.
Written by James Clark (jjc@jclark.com)
This file is part of groff.
groff is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.
groff 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 General Public License
for more details.
You should have received a copy of the GNU General Public License along
with groff; see the file COPYING. If not, write to the Free Software
Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include "lib.h"
#include "searchpath.h"
search_path::search_path(const char *envvar, const char *standard)
{
char *e = envvar ? getenv(envvar) : 0;
if (e && standard) {
dirs = new char[strlen(e) + strlen(standard) + 2];
strcpy(dirs, e);
strcat(dirs, ":");
strcat(dirs, standard);
}
else
dirs = strsave(e ? e : standard);
init_len = dirs ? strlen(dirs) : 0;
}
search_path::~search_path()
{
if (dirs)
a_delete dirs;
}
void search_path::command_line_dir(const char *s)
{
if (!dirs)
dirs = strsave(s);
else {
char *old = dirs;
unsigned old_len = strlen(old);
unsigned slen = strlen(s);
dirs = new char[old_len + 1 + slen + 1];
memcpy(dirs, old, old_len - init_len);
char *p = dirs;
p += old_len - init_len;
if (init_len == 0)
*p++ = ':';
memcpy(p, s, slen);
p += slen;
if (init_len > 0) {
*p++ = ':';
memcpy(p, old + old_len - init_len, init_len);
p += init_len;
}
*p++ = '\0';
a_delete old;
}
}
FILE *search_path::open_file(const char *name, char **pathp)
{
assert(name != 0);
if (*name == '/' || dirs == 0 || *dirs == '\0') {
FILE *fp = fopen(name, "r");
if (fp) {
if (pathp)
*pathp = strsave(name);
return fp;
}
else
return 0;
}
unsigned namelen = strlen(name);
char *p = dirs;
for (;;) {
char *end = strchr(p, ':');
if (!end)
end = strchr(p, '\0');
int need_slash = end > p && end[-1] != '/';
char *path = new char[(end - p) + need_slash + namelen + 1];
memcpy(path, p, end - p);
if (need_slash)
path[end - p] = '/';
strcpy(path + (end - p) + need_slash, name);
#if 0
fprintf(stderr, "trying `%s'\n", path);
#endif
FILE *fp = fopen(path, "r");
if (fp) {
if (pathp)
*pathp = path;
else
a_delete path;
return fp;
}
a_delete path;
if (*end == '\0')
break;
p = end + 1;
}
return 0;
}