I'm new to NaCl and now I'm starting to have some issues with this. I'm trying to load some data into C++ part of the application from C++ code and I know that I can't access files on HDD from NaCl. So, what I tried to do, was to use curl library to load this files via http from localhost.
So I set up NaCl environment, added curl - everything built fine, then I had an issue that curl couldn't resolve host name, but hopefully I overcame this issue, but then curls says that it can't connect to server (error code 7). I don't know what might be the issue.
I start chrome using this command:
google-chrome 127.0.0.1:5103/myapp --allow-nacl-socket-api=127.0.0.1
--no-sandbox --load-extension="/home/user/Desktop/nacl_sdk/pepper_49/getting_started/web/"
--enable-nacl --user-data-dir="/home/user/Desktop/chrome-dir/"
And code that is trying to load data from localhost is as follows:
static size_t data_write(char* buf, size_t size, size_t nmemb, void* userp) {
printf("start data_write\n");
if (userp) {
std::stringstream& data = *static_cast<std::stringstream*>(userp);
std::streamsize len = size * nmemb;
for (int i = 0; i < len; ++i) {
data << buf[i];
}
return len;
}
printf("end data_write\n");
return 0;
}
CURLcode curl_read(const std::string& url, std::stringstream& os, long timeout = 300) {
CURLcode code(CURLE_FAILED_INIT);
CURL* curl = curl_easy_init();
printf("CURL_READ\n");
if (curl) {
printf("curl is not null\n");
if (CURLE_OK == (code = curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
&data_write)) &&
CURLE_OK == (code = curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 1L)) &&
CURLE_OK ==
(code = curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L)) &&
CURLE_OK == (code = curl_easy_setopt(curl, CURLOPT_FILE, &os)) &&
CURLE_OK == (code = curl_easy_setopt(curl, CURLOPT_TIMEOUT, timeout)) &&
CURLE_OK == (code = curl_easy_setopt(curl, CURLOPT_URL, url.c_str()))) {
printf("START curl perform\n");
code = curl_easy_perform(curl);
printf("CURL ERROR (%d) = %s\n", code, curl_easy_strerror(code));
printf("END curl perform\n");
}
curl_easy_cleanup(curl);
}
return code;
}
And the output from console is:
Init curl
Loading data from: http://127.0.0.1/assets/model.obj
CURL_READ
curl is not null
START curl perform
CURL ERROR (7) = Couldn't connect to server
END curl perform
What might be the issue? Is it even possible to use curl in NaCl?
Related
i am new to cUrl.
What i need todo is a curl request to an ldap server.
So far the request works fine over the command line:
$curl ldap://XXXXXXXXX:389/DC=XXXXXXXXX,DC=DE?mail?sub?(sAMAccountName=XXXXXXXXX) --user s_ad_XXXXXXXXX:Password
After trying to get this done in my C++ CMake Project. I issued this error Code from
libcurl: libcurl: (39) LDAP local: ldap_search_ext Bad search filter
My code as snippet:
std::string readBuffer;
CURL* curl = curl_easy_init();
if (curl) {
CURLcode res;
char errbuf[CURL_ERROR_SIZE];
curl_easy_setopt(curl, CURLOPT_URL, "ldap://XXXXXXXXX:389/DC=XXXXXXXXX,DC=DE?mail?sub?(sAMAccountName=XXXXXXXXX) --user s_ad_XXXXXXXXX:Password");
curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, errbuf);
errbuf[0] = 0;
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L); // this line prints into console, what curl is trying to do
curl_easy_setopt(curl, CURLOPT_FORBID_REUSE, 1L); // closes the connection, if not here the connection can be used more than once
// curl_easy_setopt(curl, CURLOPT_WRITEDATA, &readBuffer);
res = curl_easy_perform(curl);
std::cout << res << std::endl;
curl_easy_cleanup(curl);
std::cout << readBuffer << std::endl;
if (res != CURLE_OK) {
size_t len = strlen(errbuf);
fprintf(stderr, "\nlibcurl: (%d) ", res);
if (len)
fprintf(stderr, "%s%s", errbuf,
((errbuf[len - 1] != '\n') ? "\n" : ""));
else
fprintf(stderr, "%s\n", curl_easy_strerror(res));
}
}
My Output:
Test curl library
* Trying XXXXXXXXXXXXXX
* TCP_NODELAY set
* Connected to XXXXXXXXXXXXXX
* LDAP local: ldap://XXXXXXXXX:389/DC=XXXXXXXXX,DC=DE?mail?sub?(sAMAccountName=XXXXXXXXX) --user s_ad_XXXXXXXXX:Password
* LDAP local: ldap_search_ext Bad search filter
* Closing connection 0
39
libcurl: (39) LDAP local: ldap_search_ext Bad search filter
I appricate every help! Thank you for taking the time reading this.
You cannot just bung everything into the CURLOPT_OPT_URL field. The --user bit should be separated into a separate parameter:
curl_easy_setopt(curl, CURLOPT_URL, "ldap://XXXXXXXXX:389/DC=XXXXXXXXX,DC=DE?mail?sub?(sAMAccountName=XXXXXXXXX)");
curl_easy_setopt(curl, CURLOPT_USERPWD, "s_ad_XXXXXXXXX:Password");
I have a binary file to be downloaded and using curl in linux terminal, the following command supports download resume on a broken request.
curl -C - -o sample1.bin https://speed.hetzner.de/100MB.bin
The above will resume a download that is canceled.
When i use libcurl in my cpp program to do the same, is there any api's that i can use to achieve the above result on a HTTPS broken request.
Thank you for you help.
NOTE: CURL_RESUME_FROM does not have support on HTTPS.
I think you could implement a retry system by yourself, for example:
CURL *curl;
curl = curl_easy_init();
//Set curl options as needed with curl_easy_setopt()
char* url;
int tries = 0;
bool done = false;
while (tries != 3 && !done) {
res = curl_easy_perform(curl);
curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &http_code);
curl_easy_getinfo(curl, CURLINFO_TOTAL_TIME, &elapsed);
curl_easy_getinfo(curl, CURLINFO_EFFECTIVE_URL, &url);
if (res != CURLE_OK || http_code != 200)
tries++;
else
done = true;
}
// Check if any error has occurred
if (res != CURLE_OK || http_code != 200) {
// Could not perform request "
if (tries == 3) {
//Too many tries, remote host is overloaded or down
} else {
// Cannot perform CURL
}
}
// Curl succeeded
Also you can have a look to CURLOPT_LOW_SPEED_LIMIT and CURLOPT_LOW_SPEED_TIME to avoid any overhead in the server.
How about something "low-level" like passing an extra header? Let s be the size of the partially-downloaded file, just use Range: bytes=s-.
See Requesting_a_specific_range_from_a_server and CURLOPT_HTTPHEADER explained.
#include <curl/curl.h>
#include <string>
#include <sstream>
int dim=... //size of partial download sample1.bin
std::string s=std::to_string(dim); // <-- here s is the string representing the size of the partial download
CURL *curl = curl_easy_init();
struct curl_slist *list = NULL;
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL,"https://speed.hetzner.de/100MB.bin");
list = curl_slist_append(list, "Range: bytes="+s+"-"); //from where it left off to the end (or where it stops again)
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, list);
curl_easy_perform(curl);
curl_slist_free_all(list); /* free the list again */
}
Check out also Making HTTPS GET with libcurl.
I want to retry a curl connection in my C++ program for 5 times. When it fails 5 times in a row, it should stop the execution of the program. However, it stops after the first error at this point. I am able to catch the error, however I don't know how to execute the previous curl connection. E.g., with jQuery I can use something like $.ajax(this);. For LibCurl in C++ I am looking for a similar solution.
My current LibCurl code is shown below, note that I use multiple curl connections which all have other settings, therefore I would like a general approach which I can use for all my LibCurl errors within my LibcurlError function which is also included below.
curl = curl_easy_init();
if (curl) {
CurlResponse = "";
host = "http://google.com";
LibcurlHeaders = curl_slist_append(NULL, "Expect:");
if (ProxyAddress.length() > 0) {
curl_easy_setopt(curl, CURLOPT_PROXY, ProxyAddress.c_str());
}
curl_easy_setopt(curl, CURLOPT_URL, (host).c_str());
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER , 1);
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST , 1);
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, LibcurlHeaders);
res = curl_easy_perform(curl);
curl_slist_free_all(LibcurlHeaders);
if (res != CURLE_OK) {
//AT THIS POINT I WOULD LIKE TO RETRY FOR 5 TIMES WHICH I WOULD LIKE TO CATCH IN MY LibcurlError FUNCTION.
LibcurlError(curl_easy_strerror(res), host);
}
curl_easy_cleanup(curl);
}
curl_global_cleanup();
void LibcurlError(string error, string host) {
//IF FAILED FOR LESS THEN 5 TIMES IN A ROW -> RETRY CURL
//ELSE I WOULD LIKE TO EXECUTE MY ORIGINAL CODE WHICH IS STATED BELOW
Message = "LibCurl Error: ";
if (error == "Couldn't resolve host name") {
Message.append("Couldn't connect to the server of ");
if (host.find("google.com") != string::npos) {
Message.append("Google");
}
else {
Message.append("'" + host + "'");
}
}
else {
Message.append("'" + error + "'");
}
cout << Message << endl;
system("pause");
exit(0);
}
There is no CURL method that specifically does this because it can be accomplished by repeated calls to curl_easy_perform.
Here is how you would write the code in your question (the relevant part at least) using loops to retry the CURL request repeatedly:
#include <unistd.h>
#include <curl/curl.h>
/*
* This is the maximum number of times CURL will run
*/
const int max_attempts = 5;
curl = curl_easy_init();
if (curl) {
CurlResponse = "";
host = "http://google.com";
LibcurlHeaders = curl_slist_append(NULL, "Expect:");
if (ProxyAddress.length() > 0) {
curl_easy_setopt(curl, CURLOPT_PROXY, ProxyAddress.c_str());
}
curl_easy_setopt(curl, CURLOPT_URL, (host).c_str());
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER , 1);
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST , 1);
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, LibcurlHeaders);
for (int i = 1; i <= max_attempts &&
(res = curl_easy_perform(curl)) != CURLE_OK; i++) {
/*
* At this point, you would sleep
* for some seconds between requests
*/
const int sleep_secs = 1;
sleep(sleep_secs);
}
// As others have mentioned, you should delete this line:
//curl_slist_free_all(LibcurlHeaders);
if (res != CURLE_OK) {
// The max retries have all failed
LibcurlError(curl_easy_strerror(res), host);
}
else {
// The request has succeeded in the first `max_retries` attempts
// ...
}
curl_easy_cleanup(curl);
}
curl_global_cleanup();
I’m writing the program sending POST-requests to the server and getting answers from it. (using curl library) (OS Linux, Red Hat Linux 3.2.2.-5). Sometimes I see , that response from server contains only second part of the message. ( I print _sResponse and sometimes I see full message(more often) and sometimes broken message(only last part of it)).
Class CurlSoapHandler
{
……..
static std::string _sResponse;
static std::string GetResponse() {return _sResponse;}
static size_t write_data(char *ptr, size_t size, size_t count, std::string *buffer)
{
int result = 0;
if (buffer != NULL)
{
std::string tmp_buffer(ptr, size * count);
_sResponse = tmp_buffer;
result = size * count;
}
else
{
std::cout<<"Buffer is not OK!"<<std::endl;
}
return result;
}
};
void CurlSoapHandler::DoRequest(const std::string& sRequest, std::string& sResponse)
{
CURL* _CURL;
CURLcode res;
struct curl_slist *headerlist=NULL;
headerlist = curl_slist_append(headerlist, "Content-Type:text/xml");
curl_global_init(CURL_GLOBAL_ALL);
_CURL = curl_easy_init();
if(_CURL)
{
curl_easy_setopt( _CURL, CURLOPT_URL, ttp://10.10.10.11:8083/Server/Server.asmx);
curl_easy_setopt( _CURL, CURLOPT_USERPWD, "user#password");
curl_easy_setopt( _CURL, CURLOPT_POSTFIELDS, sRequest.c_str());
curl_easy_setopt( _CURL, CURLOPT_HTTPHEADER, headerlist);
curl_easy_setopt( _CURL, CURLOPT_TIMEOUT, 20);
curl_easy_setopt( _CURL, CURLOPT_WRITEFUNCTION, CurlSoapHandler::write_data);
res = curl_easy_perform(_CURL);
sResponse = GetResponse();
if(res != CURLE_OK)
{
std::cerr<<"CURL message: "<<curl_easy_strerror(res)<<std::endl;
}
curl_easy_cleanup(_CURL);
}
else
{
std::cout<<"Curl initialization problem!"<<std::endl;
}
curl_global_cleanup();
curl_slist_free_all (headerlist);
}
I have no ideas why it occurs. Does someone have ideas? (May be it’s necessary to set some curl options, for example). How can I determine the reason for it and understand if it’s problem of my applications or not. I'd caught traffic using tcpdump utility (I run it on my Virtual Machine (VMWARe)) and saw full message in the dump. So, I think that server sends the correct response. Thanks in advance!
Just replace _sResponse = tmp_buffer; by _sResponse += tmp_buffer; shoulds work.
In windows, this code works file, but now, I want to convert it into ubuntu:
// callback read function to upload file from local to ftp server
size_t read_callback (void* ptr, size_t size, size_t nmemb, FILE *stream){
//return fread(ptr,size,nmemb, (FILE*) stream);
return fread(ptr,size,nmemb,stream);
}
// get file name from a path
string FTPClientConnector::getFileName(string path){
int length = path.size();
for(int i = length - 1; i >= 0; i--){
if(path[i] == '/' || path[i] == '\\'){
return path.substr(i+1, length-i-1);
}
}
}
//function to upload a file to FTP server
int FTPClientConnector::uploadFile(string filePath, string serverPath ){
CURL *curl;
CURLcode res;
FILE *hd_src;
struct stat file_info;
curl_off_t fsize;
char* local_file = new char[filePath.size()+1];
std::copy(filePath.begin(), filePath.end(), local_file);
local_file[filePath.size()] = '\0';
// stat the local file
if(stat(local_file, &file_info)){
printf("couldn't open file\n");
delete local_file;
return -1;
}
// convert URL and username and password to connect to remote server
string urlPath = this->hostName + serverPath;
urlPath += getFileName(filePath);
char *url = new char[urlPath.size() + 1];
std::copy(urlPath.begin(), urlPath.end(), url);
url[urlPath.size()] = '\0';
string userAndPassString = this->userName + ":" + this->password;
char* usernameAndPassword = new char[userAndPassString.size() +1];
std::copy(userAndPassString.begin(), userAndPassString.end(), usernameAndPassword);
usernameAndPassword[userAndPassString.size()] = '\0';
// get the file to open
hd_src = fopen(local_file, "rb");
curl_global_init(CURL_GLOBAL_ALL);
curl = curl_easy_init();
if(curl){
/* specify target */
curl_easy_setopt(curl,CURLOPT_URL, url);
curl_easy_setopt(curl, CURLOPT_PORT, this->port);
curl_easy_setopt(curl, CURLOPT_USERPWD, usernameAndPassword);
/* we want to use our own read function */
curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_callback);
/* enable uploading */
curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
/* now specify which file to upload */
curl_easy_setopt(curl, CURLOPT_READDATA, hd_src);
/* Now run off and do what you've been told! */
res = curl_easy_perform(curl);
if(res != CURLE_OK){
printf("Upload file failed!\n");
delete local_file;
delete url;
delete usernameAndPassword;
return -1;
}
curl_easy_cleanup(curl);
}
fclose(hd_src);
delete local_file;
delete url;
delete usernameAndPassword;
return 0;
}
This is what I call in main.cpp:
FTPClientConnector connector(host,user,password,port);
connector.uploadFile("xml/kingfisher.xml", "/xml_test_upload");
The code above doesn't work in Ubuntu with errors:
220 ProFTPD 1.3.4a Server (Debian) [::ffff:10.244.31.244]
500 PUT not understood
500 AUTHORIZATION: not understood
500 HOST: not understood
550 */*: Forbidden command argument
500 TRANSFER-ENCODING: not understood
500 EXPECT: not understood
500 Invalid command: try being more creative
500 2A2 not understood
Edit: This is my Makefile:
uploader:
g++ -o uploader FTPClientConnector.cpp main.cpp -lcurl
The output seems to indicate that you speak HTTP to a FTP server. Make sure your URL properly uses a FTP:// prefix for FTP, as without a protocol prefix libcurl guesses which protocol you want and it defaults to HTTP...
It appears from your comments that you need to use IPv4. Add this to your list of setopt calls:
curl_easy_setopt(curl, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);