/*******************************************************************************

 * Copyright (c) 2002 - 2005 QNX Software Systems and others.

 * All rights reserved. This program and the accompanying materials

 * are made available under the terms of the Eclipse Public License v1.0

 * which accompanies this distribution, and is available at

 * http://www.eclipse.org/legal/epl-v10.html

 *

 * Contributors:

 *     QNX Software Systems - initial API and implementation

 *******************************************************************************/

/*

 * pfind.c - Search for a binary in $PATH.

 */

#include <stdio.h>

#include <unistd.h>

#include <stdlib.h>

#include <string.h>

#include <limits.h>

#ifndef PATH_MAX

#define PATH_MAX 1024

#endif

char * pfind(const char *name)

{

	char *tok;

	char *sp;

	char *path;

	char fullpath[PATH_MAX+1];

	/* Sanity check.  */

	if (name == NULL) {

		fprintf(stderr, "pfind(): Null argument.\n");

		return NULL;

	}

	/* For absolute name or name with a path, check if it is an executable.  */

	if (name[0] == '/' || name[0] == '.') {

		if (access(name, X_OK | R_OK) == 0) {

			return strdup(name);

		}

		return NULL;

	}

	/* Search in the PATH environment.  */

	path = getenv("PATH" );

	if (path == NULL || strlen(path) <= 0) {

		fprintf(stderr, "Unable to get $PATH.\n");

		return NULL;

	}

	/* The value return by getenv() is readonly */

	path = strdup(path);

	tok = strtok_r(path, ":", &sp);

	while (tok != NULL) {

		snprintf(fullpath, sizeof(fullpath) - 1, "%s/%s", tok, name);

		if (access(fullpath, X_OK | R_OK) == 0) {

			free(path);

			return strdup(fullpath);

		}

		tok = strtok_r( NULL, ":", &sp );

	}

	free(path);

	return NULL;

}

#ifdef BUILD_WITH_MAIN

int main(int argc, char **argv)

{

   int i;

   char *fullpath;

   for (i=1; i<argc; i++) {

      fullpath = pfind(argv[i]);

      if (fullpath == NULL)

        printf("Unable to find %s in $PATH.\n", argv[i]);

      else 

        printf("Found %s @ %s.\n", argv[i], fullpath);

   }

}

#endif