retriever.cpp
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00001 /*
00002  * Copyright (C) 2009, Willow Garage, Inc.
00003  *
00004  * Redistribution and use in source and binary forms, with or without
00005  * modification, are permitted provided that the following conditions are met:
00006  *   * Redistributions of source code must retain the above copyright notice,
00007  *     this list of conditions and the following disclaimer.
00008  *   * Redistributions in binary form must reproduce the above copyright
00009  *     notice, this list of conditions and the following disclaimer in the
00010  *     documentation and/or other materials provided with the distribution.
00011  *   * Neither the names of Stanford University or Willow Garage, Inc. nor the names of its
00012  *     contributors may be used to endorse or promote products derived from
00013  *     this software without specific prior written permission.
00014  *
00015  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
00016  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
00017  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
00018  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
00019  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
00020  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
00021  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
00022  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
00023  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
00024  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
00025  * POSSIBILITY OF SUCH DAMAGE.
00026  */
00027 
00028 #include "resource_retriever/retriever.h"
00029 
00030 #include <string.h>
00031 
00032 #include <ros/package.h>
00033 #include <ros/console.h>
00034 
00035 #include <curl/curl.h>
00036 
00037 namespace resource_retriever
00038 {
00039 
00040 class CURLStaticInit
00041 {
00042 public:
00043   CURLStaticInit()
00044   : initialized_(false)
00045   {
00046     CURLcode ret = curl_global_init(CURL_GLOBAL_ALL);
00047     if (ret != 0)
00048     {
00049       ROS_ERROR("Error initializing libcurl! retcode = %d", ret);
00050     }
00051     else
00052     {
00053       initialized_ = true;
00054     }
00055   }
00056 
00057   ~CURLStaticInit()
00058   {
00059     if (initialized_)
00060     {
00061       curl_global_cleanup();
00062     }
00063   }
00064 
00065   bool initialized_;
00066 };
00067 static CURLStaticInit g_curl_init;
00068 
00069 Retriever::Retriever()
00070 {
00071   curl_handle_ = curl_easy_init();
00072 }
00073 
00074 Retriever::~Retriever()
00075 {
00076   if (curl_handle_)
00077   {
00078     curl_easy_cleanup(curl_handle_);
00079   }
00080 }
00081 
00082 struct MemoryBuffer
00083 {
00084   std::vector<uint8_t> v;
00085 };
00086 
00087 size_t curlWriteFunc(void* buffer, size_t size, size_t nmemb, void* userp)
00088 {
00089   MemoryBuffer* membuf = (MemoryBuffer*)userp;
00090 
00091   size_t prev_size = membuf->v.size();
00092   membuf->v.resize(prev_size + size * nmemb);
00093   memcpy(&membuf->v[prev_size], buffer, size * nmemb);
00094 
00095   return size * nmemb;
00096 }
00097 
00098 MemoryResource Retriever::get(const std::string& url)
00099 {
00100   std::string mod_url = url;
00101   if (url.find("package://") == 0)
00102   {
00103     mod_url.erase(0, strlen("package://"));
00104     size_t pos = mod_url.find("/");
00105     if (pos == std::string::npos)
00106     {
00107       throw Exception(url, "Could not parse package:// format into file:// format");
00108     }
00109 
00110     std::string package = mod_url.substr(0, pos);
00111     mod_url.erase(0, pos);
00112     std::string package_path = ros::package::getPath(package);
00113 
00114     if (package_path.empty())
00115     {
00116       throw Exception(url, "Package [" + package + "] does not exist");
00117     }
00118 
00119     mod_url = "file://" + package_path + mod_url;
00120   }
00121 
00122   curl_easy_setopt(curl_handle_, CURLOPT_URL, mod_url.c_str());
00123   curl_easy_setopt(curl_handle_, CURLOPT_WRITEFUNCTION, curlWriteFunc);
00124 
00125   char error_buffer[CURL_ERROR_SIZE];
00126   curl_easy_setopt(curl_handle_, CURLOPT_ERRORBUFFER , error_buffer);
00127 
00128   MemoryResource res;
00129   MemoryBuffer buf;
00130   curl_easy_setopt(curl_handle_, CURLOPT_WRITEDATA, &buf);
00131 
00132   CURLcode ret = curl_easy_perform(curl_handle_);
00133   if (ret != 0)
00134   {
00135     throw Exception(mod_url, error_buffer);
00136   }
00137   else if (!buf.v.empty())
00138   {
00139     res.size = buf.v.size();
00140     res.data.reset(new uint8_t[res.size]);
00141     memcpy(res.data.get(), &buf.v[0], res.size);
00142   }
00143 
00144   return res;
00145 }
00146 
00147 }


resource_retriever
Author(s): Josh Faust
autogenerated on Thu Aug 27 2015 14:40:57