thodg/libgit2

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b8aa163..fa5456e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -60,7 +60,6 @@ OPTION(USE_HTTPS			"Enable HTTPS support. Can be set to a specific backend" ON)
 OPTION(USE_GSSAPI			"Link with libgssapi for SPNEGO auth"			OFF)
 OPTION(USE_STANDALONE_FUZZERS		"Enable standalone fuzzers (compatible with gcc)"	OFF)
 OPTION(VALGRIND				"Configure build for valgrind"				OFF)
-OPTION(CURL				"Use curl for HTTP if available"			 ON)
 OPTION(USE_EXT_HTTP_PARSER		"Use system HTTP_Parser if available"			 ON)
 OPTION(DEBUG_POOL			"Enable debug pool allocator"				OFF)
 OPTION(ENABLE_WERROR			"Enable compilation with -Werror"			OFF)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 8ba3aa5..5ad8b14 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -125,17 +125,6 @@ IF (WIN32 AND WINHTTP)
 
 	LIST(APPEND LIBGIT2_LIBS "rpcrt4" "crypt32" "ole32")
 	LIST(APPEND LIBGIT2_PC_LIBS "-lrpcrt4" "-lcrypt32" "-lole32")
-ELSE ()
-	IF (CURL)
-		FIND_PKGLIBRARIES(CURL libcurl)
-	ENDIF ()
-	IF (CURL_FOUND)
-		SET(GIT_CURL 1)
-		LIST(APPEND LIBGIT2_SYSTEM_INCLUDES ${CURL_INCLUDE_DIRS})
-		LIST(APPEND LIBGIT2_LIBS ${CURL_LIBRARIES})
-		LIST(APPEND LIBGIT2_PC_LIBS ${CURL_LDFLAGS})
-	ENDIF()
-	ADD_FEATURE_INFO(cURL GIT_CURL "cURL for HTTP proxy support")
 ENDIF()
 
 IF (USE_HTTPS)
diff --git a/src/features.h.in b/src/features.h.in
index f414c58..694a61c 100644
--- a/src/features.h.in
+++ b/src/features.h.in
@@ -22,7 +22,6 @@
 
 #cmakedefine GIT_GSSAPI 1
 #cmakedefine GIT_WINHTTP 1
-#cmakedefine GIT_CURL 1
 
 #cmakedefine GIT_HTTPS 1
 #cmakedefine GIT_OPENSSL 1
diff --git a/src/global.c b/src/global.c
index fabe5f2..51d34f6 100644
--- a/src/global.c
+++ b/src/global.c
@@ -13,7 +13,6 @@
 #include "filter.h"
 #include "merge_driver.h"
 #include "streams/tls.h"
-#include "streams/curl.h"
 #include "streams/mbedtls.h"
 #include "streams/openssl.h"
 #include "thread-utils.h"
@@ -70,7 +69,6 @@ static int init_common(void)
 		(ret = git_transport_ssh_global_init()) == 0 &&
 		(ret = git_tls_stream_global_init()) == 0 &&
 		(ret = git_openssl_stream_global_init()) == 0 &&
-		(ret = git_curl_stream_global_init()) == 0 &&
 		(ret = git_mbedtls_stream_global_init()) == 0)
 		ret = git_mwindow_global_init();
 
diff --git a/src/streams/curl.c b/src/streams/curl.c
deleted file mode 100644
index 3c0af3b..0000000
--- a/src/streams/curl.c
+++ /dev/null
@@ -1,385 +0,0 @@
-/*
- * Copyright (C) the libgit2 contributors. All rights reserved.
- *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
- * a Linking Exception. For full terms see the included COPYING file.
- */
-
-#include "streams/curl.h"
-
-#ifdef GIT_CURL
-
-#include <curl/curl.h>
-
-#include "stream.h"
-#include "git2/transport.h"
-#include "buffer.h"
-#include "global.h"
-#include "vector.h"
-#include "proxy.h"
-
-/* This is for backwards compatibility with curl<7.45.0. */
-#ifndef CURLINFO_ACTIVESOCKET
-# define CURLINFO_ACTIVESOCKET CURLINFO_LASTSOCKET
-# define GIT_CURL_BADSOCKET -1
-# define git_activesocket_t long
-#else
-# define GIT_CURL_BADSOCKET CURL_SOCKET_BAD
-# define git_activesocket_t curl_socket_t
-#endif
-
-typedef struct {
-	git_stream parent;
-	CURL *handle;
-	curl_socket_t socket;
-	char curl_error[CURL_ERROR_SIZE + 1];
-	git_cert_x509 cert_info;
-	git_strarray cert_info_strings;
-	git_proxy_options proxy;
-	git_cred *proxy_cred;
-} curl_stream;
-
-int git_curl_stream_global_init(void)
-{
-	if (curl_global_init(CURL_GLOBAL_ALL) != 0) {
-		giterr_set(GITERR_NET, "could not initialize curl");
-		return -1;
-	}
-
-	/* `curl_global_cleanup` is provided by libcurl */
-	git__on_shutdown(curl_global_cleanup);
-	return 0;
-}
-
-static int seterr_curl(curl_stream *s)
-{
-	giterr_set(GITERR_NET, "curl error: %s\n", s->curl_error);
-	return -1;
-}
-
-GIT_INLINE(int) error_no_credentials(void)
-{
-	giterr_set(GITERR_NET, "proxy authentication required, but no callback provided");
-	return GIT_EAUTH;
-}
-
-static int apply_proxy_creds(curl_stream *s)
-{
-	CURLcode res;
-	git_cred_userpass_plaintext *userpass;
-
-	if (!s->proxy_cred)
-		return GIT_ENOTFOUND;
-
-	userpass = (git_cred_userpass_plaintext *) s->proxy_cred;
-	if ((res = curl_easy_setopt(s->handle, CURLOPT_PROXYUSERNAME, userpass->username)) != CURLE_OK)
-		return seterr_curl(s);
-	if ((res = curl_easy_setopt(s->handle, CURLOPT_PROXYPASSWORD, userpass->password)) != CURLE_OK)
-		return seterr_curl(s);
-
-	return 0;
-}
-
-static int ask_and_apply_proxy_creds(curl_stream *s)
-{
-	int error;
-	git_proxy_options *opts = &s->proxy;
-
-	if (!opts->credentials)
-		return error_no_credentials();
-
-	/* TODO: see if PROXYAUTH_AVAIL helps us here */
-	git_cred_free(s->proxy_cred);
-	s->proxy_cred = NULL;
-	giterr_clear();
-	error = opts->credentials(&s->proxy_cred, opts->url, NULL, GIT_CREDTYPE_USERPASS_PLAINTEXT, opts->payload);
-	if (error == GIT_PASSTHROUGH)
-		return error_no_credentials();
-	if (error < 0) {
-		if (!giterr_last())
-			giterr_set(GITERR_NET, "proxy authentication was aborted by the user");
-		return error;
-	}
-
-	if (s->proxy_cred->credtype != GIT_CREDTYPE_USERPASS_PLAINTEXT) {
-		giterr_set(GITERR_NET, "credentials callback returned invalid credential type");
-		return -1;
-	}
-
-	return apply_proxy_creds(s);
-}
-
-static int curls_connect(git_stream *stream)
-{
-	curl_stream *s = (curl_stream *) stream;
-	git_activesocket_t sockextr;
-	long connect_last = 0;
-	int failed_cert = 0, error;
-	bool retry_connect;
-	CURLcode res;
-
-	/* Apply any credentials we've already established */
-	error = apply_proxy_creds(s);
-	if (error < 0 && error != GIT_ENOTFOUND)
-		return seterr_curl(s);
-
-	do {
-		retry_connect = 0;
-		res = curl_easy_perform(s->handle);
-
-		curl_easy_getinfo(s->handle, CURLINFO_HTTP_CONNECTCODE, &connect_last);
-
-		/* HTTP 407 Proxy Authentication Required */
-		if (connect_last == 407) {
-			if ((error = ask_and_apply_proxy_creds(s)) < 0)
-				return error;
-
-			retry_connect = true;
-		}
-	} while (retry_connect);
-
-	if (res != CURLE_OK && res != CURLE_PEER_FAILED_VERIFICATION)
-		return seterr_curl(s);
-	if (res == CURLE_PEER_FAILED_VERIFICATION)
-		failed_cert = 1;
-
-	if ((res = curl_easy_getinfo(s->handle, CURLINFO_ACTIVESOCKET, &sockextr)) != CURLE_OK) {
-		return seterr_curl(s);
-	}
-
-	if (sockextr == GIT_CURL_BADSOCKET) {
-		giterr_set(GITERR_NET, "curl socket is no longer valid");
-		return -1;
-	}
-
-	s->socket = sockextr;
-
-	if (s->parent.encrypted && failed_cert)
-		return GIT_ECERTIFICATE;
-
-	return 0;
-}
-
-static int curls_certificate(git_cert **out, git_stream *stream)
-{
-	int error;
-	CURLcode res;
-	struct curl_slist *slist;
-	struct curl_certinfo *certinfo;
-	git_vector strings = GIT_VECTOR_INIT;
-	curl_stream *s = (curl_stream *) stream;
-
-	if ((res = curl_easy_getinfo(s->handle, CURLINFO_CERTINFO, &certinfo)) != CURLE_OK)
-		return seterr_curl(s);
-
-	/* No information is available, can happen with SecureTransport */
-	if (certinfo->num_of_certs == 0) {
-		s->cert_info.parent.cert_type = GIT_CERT_NONE;
-		s->cert_info.data             = NULL;
-		s->cert_info.len              = 0;
-		return 0;
-	}
-
-	if ((error = git_vector_init(&strings, 8, NULL)) < 0)
-		return error;
-
-	for (slist = certinfo->certinfo[0]; slist; slist = slist->next) {
-		char *str = git__strdup(slist->data);
-		GITERR_CHECK_ALLOC(str);
-		git_vector_insert(&strings, str);
-	}
-
-	/* Copy the contents of the vector into a strarray so we can expose them */
-	s->cert_info_strings.strings = (char **) strings.contents;
-	s->cert_info_strings.count   = strings.length;
-
-	s->cert_info.parent.cert_type = GIT_CERT_STRARRAY;
-	s->cert_info.data             = &s->cert_info_strings;
-	s->cert_info.len              = strings.length;
-
-	*out = &s->cert_info.parent;
-
-	return 0;
-}
-
-static int curls_set_proxy(git_stream *stream, const git_proxy_options *proxy_opts)
-{
-	int error;
-	CURLcode res;
-	curl_stream *s = (curl_stream *) stream;
-
-	git_proxy_options_clear(&s->proxy);
-	if ((error = git_proxy_options_dup(&s->proxy, proxy_opts)) < 0)
-		return error;
-
-	if ((res = curl_easy_setopt(s->handle, CURLOPT_PROXY, s->proxy.url)) != CURLE_OK)
-		return seterr_curl(s);
-
-	if ((res = curl_easy_setopt(s->handle, CURLOPT_PROXYAUTH, CURLAUTH_ANY)) != CURLE_OK)
-		return seterr_curl(s);
-
-	return 0;
-}
-
-static int wait_for(curl_socket_t fd, bool reading)
-{
-	int ret;
-	fd_set infd, outfd, errfd;
-
-	FD_ZERO(&infd);
-	FD_ZERO(&outfd);
-	FD_ZERO(&errfd);
-
-	assert(fd >= 0);
-	FD_SET(fd, &errfd);
-	if (reading)
-		FD_SET(fd, &infd);
-	else
-		FD_SET(fd, &outfd);
-
-	if ((ret = select(fd + 1, &infd, &outfd, &errfd, NULL)) < 0) {
-		giterr_set(GITERR_OS, "error in select");
-		return -1;
-	}
-
-	return 0;
-}
-
-static ssize_t curls_write(git_stream *stream, const char *data, size_t len, int flags)
-{
-	int error;
-	size_t off = 0, sent;
-	CURLcode res;
-	curl_stream *s = (curl_stream *) stream;
-
-	GIT_UNUSED(flags);
-
-	do {
-		if ((error = wait_for(s->socket, false)) < 0)
-			return error;
-
-		res = curl_easy_send(s->handle, data + off, len - off, &sent);
-		if (res == CURLE_OK)
-			off += sent;
-	} while ((res == CURLE_OK || res == CURLE_AGAIN) && off < len);
-
-	if (res != CURLE_OK)
-		return seterr_curl(s);
-
-	return len;
-}
-
-static ssize_t curls_read(git_stream *stream, void *data, size_t len)
-{
-	int error;
-	size_t read;
-	CURLcode res;
-	curl_stream *s = (curl_stream *) stream;
-
-	do {
-		if ((error = wait_for(s->socket, true)) < 0)
-			return error;
-
-		res = curl_easy_recv(s->handle, data, len, &read);
-	} while (res == CURLE_AGAIN);
-
-	if (res != CURLE_OK)
-		return seterr_curl(s);
-
-	return read;
-}
-
-static int curls_close(git_stream *stream)
-{
-	curl_stream *s = (curl_stream *) stream;
-
-	if (!s->handle)
-		return 0;
-
-	curl_easy_cleanup(s->handle);
-	s->handle = NULL;
-	s->socket = 0;
-
-	return 0;
-}
-
-static void curls_free(git_stream *stream)
-{
-	curl_stream *s = (curl_stream *) stream;
-
-	curls_close(stream);
-	git_strarray_free(&s->cert_info_strings);
-	git_proxy_options_clear(&s->proxy);
-	git_cred_free(s->proxy_cred);
-	git__free(s);
-}
-
-int git_curl_stream_new(git_stream **out, const char *host, const char *port)
-{
-	curl_stream *st;
-	CURL *handle;
-	int iport = 0, error;
-
-	st = git__calloc(1, sizeof(curl_stream));
-	GITERR_CHECK_ALLOC(st);
-
-	handle = curl_easy_init();
-	if (handle == NULL) {
-		giterr_set(GITERR_NET, "failed to create curl handle");
-		git__free(st);
-		return -1;
-	}
-
-	if ((error = git__strntol32(&iport, port, strlen(port), NULL, 10)) < 0) {
-		git__free(st);
-		return error;
-	}
-
-	curl_easy_setopt(handle, CURLOPT_URL, host);
-	curl_easy_setopt(handle, CURLOPT_ERRORBUFFER, st->curl_error);
-	curl_easy_setopt(handle, CURLOPT_PORT, iport);
-	curl_easy_setopt(handle, CURLOPT_CONNECT_ONLY, 1);
-	curl_easy_setopt(handle, CURLOPT_SSL_VERIFYPEER, 1);
-	curl_easy_setopt(handle, CURLOPT_CERTINFO, 1);
-	curl_easy_setopt(handle, CURLOPT_HTTPPROXYTUNNEL, 1);
-	curl_easy_setopt(handle, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
-
-	/* curl_easy_setopt(handle, CURLOPT_VERBOSE, 1); */
-
-	st->parent.version = GIT_STREAM_VERSION;
-	st->parent.encrypted = 0; /* we don't encrypt ourselves */
-	st->parent.proxy_support = 1;
-	st->parent.connect = curls_connect;
-	st->parent.certificate = curls_certificate;
-	st->parent.set_proxy = curls_set_proxy;
-	st->parent.read = curls_read;
-	st->parent.write = curls_write;
-	st->parent.close = curls_close;
-	st->parent.free = curls_free;
-	st->handle = handle;
-
-	*out = (git_stream *) st;
-	return 0;
-}
-
-#else
-
-#include "stream.h"
-
-int git_curl_stream_global_init(void)
-{
-	return 0;
-}
-
-int git_curl_stream_new(git_stream **out, const char *host, const char *port)
-{
-	GIT_UNUSED(out);
-	GIT_UNUSED(host);
-	GIT_UNUSED(port);
-
-	giterr_set(GITERR_NET, "curl is not supported in this version");
-	return -1;
-}
-
-
-#endif
diff --git a/src/streams/curl.h b/src/streams/curl.h
deleted file mode 100644
index 511cd89..0000000
--- a/src/streams/curl.h
+++ /dev/null
@@ -1,17 +0,0 @@
-/*
- * Copyright (C) the libgit2 contributors. All rights reserved.
- *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
- * a Linking Exception. For full terms see the included COPYING file.
- */
-#ifndef INCLUDE_streams_curl_h__
-#define INCLUDE_streams_curl_h__
-
-#include "common.h"
-
-#include "git2/sys/stream.h"
-
-extern int git_curl_stream_global_init(void);
-extern int git_curl_stream_new(git_stream **out, const char *host, const char *port);
-
-#endif
diff --git a/src/streams/mbedtls.c b/src/streams/mbedtls.c
index fdc9f6f..d22f770 100644
--- a/src/streams/mbedtls.c
+++ b/src/streams/mbedtls.c
@@ -18,10 +18,6 @@
 #include "git2/transport.h"
 #include "util.h"
 
-#ifdef GIT_CURL
-# include "streams/curl.h"
-#endif
-
 #ifndef GIT_DEFAULT_CERT_LOCATION
 #define GIT_DEFAULT_CERT_LOCATION NULL
 #endif
@@ -431,13 +427,7 @@ int git_mbedtls_stream_new(
 
 	assert(out && host && port);
 
-#ifdef GIT_CURL
-	error = git_curl_stream_new(&stream, host, port);
-#else
-	error = git_socket_stream_new(&stream, host, port);
-#endif
-
-	if (error < 0)
+	if ((error = git_socket_stream_new(&stream, host, port)) < 0)
 		return error;
 
 	if ((error = mbedtls_stream_wrap(out, stream, host, 1)) < 0) {
diff --git a/src/streams/openssl.c b/src/streams/openssl.c
index e39622d..bc12921 100644
--- a/src/streams/openssl.c
+++ b/src/streams/openssl.c
@@ -19,10 +19,6 @@
 #include "git2/transport.h"
 #include "git2/sys/openssl.h"
 
-#ifdef GIT_CURL
-# include "streams/curl.h"
-#endif
-
 #ifndef GIT_WIN32
 # include <sys/types.h>
 # include <sys/socket.h>
@@ -752,13 +748,7 @@ int git_openssl_stream_new(git_stream **out, const char *host, const char *port)
 
 	assert(out && host && port);
 
-#ifdef GIT_CURL
-	error = git_curl_stream_new(&stream, host, port);
-#else
-	error = git_socket_stream_new(&stream, host, port);
-#endif
-
-	if (error < 0)
+	if ((error = git_socket_stream_new(&stream, host, port)) < 0)
 		return error;
 
 	if ((error = openssl_stream_wrap(out, stream, host, 1)) < 0) {
diff --git a/src/streams/stransport.c b/src/streams/stransport.c
index 4351623..6626e0f 100644
--- a/src/streams/stransport.c
+++ b/src/streams/stransport.c
@@ -16,7 +16,6 @@
 #include "git2/transport.h"
 
 #include "streams/socket.h"
-#include "streams/curl.h"
 
 static int stransport_error(OSStatus ret)
 {
@@ -308,11 +307,7 @@ int git_stransport_stream_new(git_stream **out, const char *host, const char *po
 
 	assert(out && host);
 
-#ifdef GIT_CURL
-	error = git_curl_stream_new(&stream, host, port);
-#else
 	error = git_socket_stream_new(&stream, host, port);
-#endif
 
 	if (!error)
 		error = stransport_wrap(out, stream, host, 1);
diff --git a/src/transports/http.c b/src/transports/http.c
index 6d2aaf9..9257722 100644
--- a/src/transports/http.c
+++ b/src/transports/http.c
@@ -21,7 +21,6 @@
 #include "auth_negotiate.h"
 #include "streams/tls.h"
 #include "streams/socket.h"
-#include "streams/curl.h"
 
 git_http_auth_scheme auth_schemes[] = {
 	{ GIT_AUTHTYPE_NEGOTIATE, "Negotiate", GIT_CREDTYPE_DEFAULT, git_http_auth_negotiate },
@@ -653,17 +652,6 @@ static int write_chunk(git_stream *io, const char *buffer, size_t len)
 	return 0;
 }
 
-static int apply_proxy_config_to_stream(
-	git_stream *stream, git_proxy_options *proxy_opts)
-{
-	/* Only set the proxy configuration on the curl stream. */
-	if (!git_stream_supports_proxy(stream) ||
-	    proxy_opts->type == GIT_PROXY_NONE)
-		return 0;
-
-	return git_stream_set_proxy(stream, proxy_opts);
-}
-
 static int load_proxy_config(http_subtransport *t)
 {
 	int error;
@@ -954,21 +942,10 @@ static int http_connect(http_subtransport *t)
 		cb_payload = t->owner->message_cb_payload;
 	}
 
-#ifdef GIT_CURL
-	if ((error = git_curl_stream_new(&stream,
-	        t->server.url.host, t->server.url.port)) < 0)
-		goto on_error;
-
-	GITERR_CHECK_VERSION(stream, GIT_STREAM_VERSION, "git_stream");
-
-	if ((error = apply_proxy_config_to_stream(stream, &t->proxy_opts)) < 0)
-		goto on_error;
-#else
 	if (url->use_ssl)
 		error = git_tls_stream_new(&stream, url->host, url->port);
 	else
 		error = git_socket_stream_new(&stream, url->host, url->port);
-#endif
 
 	if (error < 0)
 		goto on_error;