cavis/libnd4j/include/helpers/files.h

129 lines
3.5 KiB
C

/*******************************************************************************
* Copyright (c) 2015-2018 Skymind, Inc.
*
* This program and the accompanying materials are made available under the
* terms of the Apache License, Version 2.0 which is available at
* https://www.apache.org/licenses/LICENSE-2.0.
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
* SPDX-License-Identifier: Apache-2.0
******************************************************************************/
//
// Methods to lookup files in $PATH
// adopted from https://stackoverflow.com/questions/2718915/check-if-file-exists-including-on-path
//
#ifndef LIBND4J_FILES_H
#define LIBND4J_FILES_H
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
void *malloc_check(const char *what, size_t n);
char *strsave(const char *s, const char *lim);
char ** shellpath(void);
void freeshellpath (char *shellpath[]);
unsigned maxpathlen(char *path[], const char *base);
bool file_exists(char *name);
void *malloc_check(const char *what, size_t n) {
void *p = malloc(n);
if (p == NULL) {
fprintf(stderr, "Cannot allocate %zu bytes to %s\n", n, what);
exit(2);
}
return p;
}
char *strsave(const char *s, const char *lim) {
if (lim == NULL)
lim = s + strlen(s);
char *p = (char *) malloc_check("save string", lim - s + 1);
strncpy(p, s, lim-s);
p[lim-s] = '\0';
return p;
}
char ** shellpath(void) {
const char *path = getenv("PATH");
if (!path)
path = "./";
char **vector = // size is overkill
(char **) malloc_check("hold path elements", strlen(path) * sizeof(*vector));
const char *p = path;
int next = 0;
while (p) {
#ifdef _WIN32
char *q = strchr(p, ';'); // windows uses ; as delimiter
#else
char *q = strchr(p, ':'); // linux and derivatives use : as delimiter
#endif
vector[next++] = strsave(p, q);
p = q ? q + 1 : NULL;
}
vector[next] = NULL;
return vector;
}
void freeshellpath (char *shellpath[]) {
for (int i = 0; shellpath[i]; i++)
free(shellpath[i]);
free(shellpath);
}
unsigned maxpathlen(char *path[], const char *base) {
unsigned blen = strlen(base);
unsigned n = 0;
for (int i = 0; path[i]; i++) {
unsigned pn = strlen(path[i]);
if (pn > n) n = pn;
}
return blen+n+1;
}
bool file_exists(char *name){
printf("Trying file: [%s]\n", name);
FILE *file;
if (file = fopen(name, "r")) {
fclose(file);
return true;
}
return false;
}
bool checkFileInPath(const char *file) {
char *path = getenv("PATH");
char **listed = shellpath();
size_t maxlen = maxpathlen(listed, file)+1;
char *buf = (char *) malloc_check("hold path", maxlen);
bool found = false;
for (int i = 0; listed[i]; i++) {
if (strlen(listed[i]) > 0) {
#ifdef _WIN32
snprintf(buf, maxlen, "%s\\%s", listed[i], file);
#else
snprintf(buf, maxlen, "%s/%s", listed[i], file);
#endif
if (file_exists(buf)) {
found = true;
break;
}
}
}
free(buf);
freeshellpath(listed);
return found;
}
#endif //LIBND4J_FILES_H