netsurf/utils/filepath.c

334 lines
7.0 KiB
C

/*
* Copyright 2010 Vincent Sanders <vince@kyllikki.org>
*
* This file is part of NetSurf, http://www.netsurf-browser.org/
*
* NetSurf 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; version 2 of the License.
*
* NetSurf 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
/** \file
* Provides utility functions for finding readable files.
*
* These functions are intended to make finding resource files more straightforward.
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <stdarg.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include "utils/utils.h"
#include "utils/config.h"
#include "utils/filepath.h"
/** maximum number of elements in the resource vector */
#define MAX_RESPATH 128
/* exported interface documented in filepath.h */
char *filepath_vsfindfile(char *str, const char *format, va_list ap)
{
char *realpathname;
char *pathname;
int len;
pathname = malloc(PATH_MAX);
if (pathname == NULL)
return NULL; /* unable to allocate memory */
len = vsnprintf(pathname, PATH_MAX, format, ap);
if ((len < 0) || (len >= PATH_MAX)) {
/* error or output exceeded PATH_MAX length so
* operation is doomed to fail.
*/
free(pathname);
return NULL;
}
realpathname = realpath(pathname, str);
free(pathname);
if (realpathname != NULL) {
/* sucessfully expanded pathname */
if (access(realpathname, R_OK) != 0) {
/* unable to read the file */
return NULL;
}
}
return realpathname;
}
/* exported interface documented in filepath.h */
char *filepath_sfindfile(char *str, const char *format, ...)
{
va_list ap;
char *ret;
va_start(ap, format);
ret = filepath_vsfindfile(str, format, ap);
va_end(ap);
return ret;
}
/* exported interface documented in filepath.h */
char *filepath_findfile(const char *format, ...)
{
char *ret;
va_list ap;
va_start(ap, format);
ret = filepath_vsfindfile(NULL, format, ap);
va_end(ap);
return ret;
}
/* exported interface documented in filepath.h */
char *filepath_sfind(char **respathv, char *filepath, const char *filename)
{
int respathc = 0;
if ((respathv == NULL) || (respathv[0] == NULL) || (filepath == NULL))
return NULL;
while (respathv[respathc] != NULL) {
if (filepath_sfindfile(filepath, "%s/%s", respathv[respathc], filename) != NULL) {
return filepath;
}
respathc++;
}
return NULL;
}
/* exported interface documented in filepath.h */
char *filepath_find(char **respathv, const char *filename)
{
char *ret;
char *filepath;
if ((respathv == NULL) || (respathv[0] == NULL))
return NULL;
filepath = malloc(PATH_MAX);
if (filepath == NULL)
return NULL;
ret = filepath_sfind(respathv, filepath, filename);
if (ret == NULL)
free(filepath);
return ret;
}
/* exported interface documented in filepath.h */
char *filepath_sfinddef(char **respathv, char *filepath, const char *filename, const char *def)
{
char t[PATH_MAX];
char *ret;
if ((respathv == NULL) || (respathv[0] == NULL) || (filepath == NULL))
return NULL;
ret = filepath_sfind(respathv, filepath, filename);
if ((ret == NULL) && (def != NULL)) {
/* search failed, return the path specified */
ret = filepath;
if (def[0] == '~') {
snprintf(t, PATH_MAX, "%s/%s/%s", getenv("HOME"), def + 1, filename);
} else {
snprintf(t, PATH_MAX, "%s/%s", def, filename);
}
if (realpath(t, ret) == NULL) {
strcpy(ret, t);
}
}
return ret;
}
/* exported interface documented in filepath.h */
char **
filepath_generate(char * const *pathv, const char * const *langv)
{
char **respath; /* resource paths vector */
int pathc = 0;
int langc = 0;
int respathc = 0;
struct stat dstat;
char tmppath[PATH_MAX];
respath = calloc(MAX_RESPATH, sizeof(char *));
while (pathv[pathc] != NULL) {
if ((stat(pathv[pathc], &dstat) == 0) &&
S_ISDIR(dstat.st_mode)) {
/* path element exists and is a directory */
langc = 0;
while (langv[langc] != NULL) {
snprintf(tmppath, sizeof tmppath, "%s/%s", pathv[pathc],langv[langc]);
if ((stat(tmppath, &dstat) == 0) &&
S_ISDIR(dstat.st_mode)) {
/* path element exists and is a directory */
respath[respathc++] = strdup(tmppath);
}
langc++;
}
respath[respathc++] = strdup(pathv[pathc]);
}
pathc++;
}
return respath;
}
/**
* expand ${} in a string into environment variables.
*
* @param path The pathname to expand.
* @param pathlen The length of the path element.
* @return A string with the expanded path or NULL on empty expansion or error.
*/
static char *
expand_path(const char *path, int pathlen)
{
char *exp;
int explen;
int cstart = -1;
int cloop = 0;
char *envv;
int envlen;
int replen; /* length of replacement */
exp = malloc(pathlen + 1);
if (exp == NULL)
return NULL;
memcpy(exp, path, pathlen);
exp[pathlen] = 0;
explen = pathlen;
while (exp[cloop] != 0) {
if ((exp[cloop] == '$') &&
(exp[cloop + 1] == '{')) {
cstart = cloop;
cloop++;
}
if ((cstart != -1) &&
(exp[cloop] == '}')) {
replen = cloop - cstart;
exp[cloop] = 0;
envv = getenv(exp + cstart + 2);
if (envv == NULL) {
memmove(exp + cstart,
exp + cloop + 1,
explen - cloop);
explen -= replen;
} else {
char *tmp;
envlen = strlen(envv);
tmp = realloc(exp, explen + envlen - replen);
if (tmp == NULL) {
free(exp);
return NULL;
}
exp = tmp;
memmove(exp + cstart + envlen,
exp + cloop + 1,
explen - cloop );
memmove(exp + cstart, envv, envlen);
explen += envlen - replen;
}
cloop -= replen;
cstart = -1;
}
cloop++;
}
if (explen == 1) {
free(exp);
exp = NULL;
}
return exp;
}
/* exported interface documented in filepath.h */
char **
filepath_path_to_strvec(const char *path)
{
char **strvec;
int strc = 0;
const char *estart; /* path element start */
const char *eend; /* path element end */
int elen;
strvec = calloc(MAX_RESPATH, sizeof(char *));
if (strvec == NULL)
return NULL;
estart = eend = path;
while (strc < (MAX_RESPATH - 2)) {
while ( (*eend != 0) && (*eend != ':') )
eend++;
elen = eend - estart;
if (elen > 1) {
/* more than an empty colon */
strvec[strc] = expand_path(estart, elen);
if (strvec[strc] != NULL) {
/* successfully expanded an element */
strc++;
}
}
/* skip colons */
while (*eend == ':')
eend++;
/* check for termination */
if (*eend == 0)
break;
estart = eend;
}
return strvec;
}
/* exported interface documented in filepath.h */
void filepath_free_strvec(char **pathv)
{
int p = 0;
while (pathv[p] != NULL) {
free(pathv[p++]);
}
free(pathv);
}