/*
 * Copyright 2009, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "plugin/linux/envvars.h"

#include "base/logging.h"

namespace o3d {

static const unsigned int kMaxEnvVarLength = 1024;

void LoadEnvironmentVariablesFile(const char *path) {
  FILE *env_vars_file = fopen(path, "r");
  // It is not an error if the file is missing. We treat it the same as if it
  // were empty.
  if (env_vars_file) {
    char buffer[kMaxEnvVarLength];
    while (!feof(env_vars_file) ) {
      if (fgets(buffer, sizeof(buffer), env_vars_file)) {
        char *equals = strchr(buffer, '=');
        if (!equals) {
          LOG(ERROR) << "Malformed environment variables file";
          continue;
        }
        char *value = equals + 1;
        *equals = '\0';
        int length = strlen(value);
        if (value[length - 1] == '\n') {
          value[length - 1] = '\0';
        }
        if (setenv(buffer, value, 1) != 0) {
          LOG(ERROR) << "Couldn't add " << buffer << "=" << value
              << " to environment";
        } else {
          // Custom environment variables could be relevant for debugging
          // problem reports, so log this too.
          LOG(INFO) << "Defined " << buffer << "=" << value;
        }
      } else if (ferror(env_vars_file)) {
        PLOG(ERROR) << "Error reading from environment variables file";
        break;
      } else {
        break;
      }
    }
    if (fclose(env_vars_file) != 0) {
      PLOG(ERROR) << "Unable to close environment variables file";
    }
  }
}

}  // namespace o3d