Using libcurl on iOS 5 as an alternative to NSURLConnection

biasedbit picture biasedbit · Jan 27, 2012 · Viewed 7.6k times · Source

Update: NSURLConnection now seems to properly support 100-Continue. In any case, this answer contains a link to the script to build libcurl for iOS/OSX.

I'm having a bit of a hard time with NSURLConnection, given that it doesn't support Section 8.2.3 of RFC 2616 (HTTP/1.1).

Basically the client needs to be able to support sending the header Expect: 100-Continue; after sending the request headers, it must wait for a response from the server with the status code 100 before sending the POST/PUT body.

Furthermore, NSURLConnection (and consequently all libs that build on top of it) won't return any response from the server until all data is uploaded - which is a pain since the server may reject the upload right away (invalid credentials, no space, file too large, etc). While it does "work" for small files (content is fully uploaded and delegate method with response is called), on large files instead of getting the error response from the server (which I am positively sure is sent), I just get a "Connection failed" error.

I know libcurl properly supports the 100-Continue spec so I need some help compiling it and getting it up and running on a iOS 5 project.

I started with this post(scroll to bottom) but I couldn't get far...

Made these changes...

export CC=/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/llvm-gcc-4.2
export CFLAGS="-arch armv7 --sysroot=/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.0.sdk"
export CPP=/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/llvm-cpp-4.2
export AR=/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/ar
./configure --disable-shared --without-ssl --without-libssh2 --without-ca-bundle --without-ldap --disable-ldap --host=arm-apple-darwin10 --build=arm-apple-darwin10
make clean
make
ar rv libcurl.armv7.a lib/*.o

... but compilation fails with message

(...)
checking for arm-apple-darwin10-gcc... /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/llvm-gcc-4.2
checking whether the C compiler works... no
configure: error: in `/Users/bruno/Downloads/curl-7.21.4':
configure: error: C compiler cannot create executables

I'm using curl 7.21.4, downloaded from Apple's open source site.

So, how can I compile curl and use it on a iOS 5 project, preferably with SSL support?

Answer

Bob picture Bob · Mar 2, 2012

This worked for me with the latest SDK:

#!/bin/sh 
export SDK=5.0

buildit()
{
    target=$1
    platform=$2

    export CC=/Developer/Platforms/${platform}.platform/Developer/usr/bin/gcc
    export CFLAGS="-arch ${target} -isysroot /Developer/Platforms/${platform}.platform/Developer/SDKs/${platform}${SDK}.sdk"
    export CPP="/Developer/Platforms/${platform}.platform/Developer/usr/bin/llvm-cpp-4.2"
    export AR=/Developer/Platforms/${platform}.platform/Developer/usr/bin/ar
    export RANLIB=/Developer/Platforms/${platform}.platform/Developer/usr/bin/ranlib

    ./configure --disable-shared --without-ssl --without-libssh2 --without-ca-bundle --without-ldap --disable-ldap \
            --host=${target}-apple-darwin10

    make clean
    make
    $AR rv libcurl.${target}.a lib/*.o
}

buildit armv6 iPhoneOS
buildit armv7 iPhoneOS
buildit i386 iPhoneSimulator

lipo -create libcurl.armv7.a libcurl.armv6.a libcurl.i386.a -output libcurl.a