104 lines
3.3 KiB
C
104 lines
3.3 KiB
C
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/**
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* @file find_program.h
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* @author Ambroz Bizjak <ambrop7@gmail.com>
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*
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* @section LICENSE
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the author nor the
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* names of its contributors may be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
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* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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* @section DESCRIPTION
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*
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* Function that finds the absolute path of a program by checking a predefined
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* list of directories.
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*/
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#ifndef BADVPN_FIND_PROGRAM_H
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#define BADVPN_FIND_PROGRAM_H
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#include <stdlib.h>
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#include <unistd.h>
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#include <string.h>
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#include <misc/concat_strings.h>
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#include <misc/debug.h>
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#include <misc/balloc.h>
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static char * badvpn_find_program (const char *name);
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static char * badvpn_find_program (const char *name)
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{
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ASSERT(name)
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char *path = getenv("PATH");
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if (path) {
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while (1) {
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size_t i = 0;
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while (path[i] != ':' && path[i] != '\0') {
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i++;
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}
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char const *src = path;
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size_t src_len = i;
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if (src_len == 0) {
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src = ".";
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src_len = 1;
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}
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size_t name_len = strlen(name);
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char *entry = BAllocSize(bsize_add(bsize_fromsize(src_len), bsize_add(bsize_fromsize(name_len), bsize_fromsize(2))));
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if (!entry) {
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goto fail;
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}
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memcpy(entry, src, src_len);
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entry[src_len] = '/';
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strcpy(entry + (src_len + 1), name);
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if (access(entry, X_OK) == 0) {
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return entry;
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}
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free(entry);
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if (path[i] == '\0') {
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break;
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}
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path += i + 1;
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}
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}
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const char *dirs[] = {"/usr/sbin", "/usr/bin", "/sbin", "/bin", NULL};
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for (size_t i = 0; dirs[i]; i++) {
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char *path = concat_strings(3, dirs[i], "/", name);
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if (!path) {
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goto fail;
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}
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if (access(path, X_OK) == 0) {
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return path;
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}
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free(path);
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}
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fail:
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return NULL;
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}
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#endif
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