basic http implementation

CMakeLists.txt

@@ -5,6 +5,8 @@ list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/cmake")
 find_package(libev REQUIRED)
 find_package(libtls REQUIRED)
 
+set(CMAKE_BUILD_TYPE RelWithDebInfo)
+
 include(AddAutoformatTarget)
 include(Makeheaders)
 

src/CMakeLists.txt

@@ -1,7 +1,8 @@
 add_executable(${PROJECT_NAME}
-  main.c
-  connection.c
   buffer.c
+  connection.c
+  http.c
+  main.c
 )
 target_link_libraries(${PROJECT_NAME}
   libev::ev

src/buffer.c

@@ -1,4 +1,6 @@
 #include <buffer.h>
+#include <stdarg.h>
+#include <stdio.h>
 #include <string.h>
 
 #if INTERFACE
@@ -11,7 +13,7 @@ struct Buffer {
 };
 
 #define buffer_size(buffer) ((buffer)->size)
-#define buffer_capacity(buffer) (sizeof(buffer)->data)
+#define buffer_capacity(buffer) (sizeof((buffer)->data))
 #define buffer_data(buffer) ((buffer)->data)
 
 #endif
@@ -25,7 +27,25 @@ void buffer_provide(Buffer *buffer, size_t n) {
   buffer->size += n;
 }
 
-size_t buffer_size_remaining(Buffer *buffer) {
+int buffer_printf(Buffer *buffer, const char *format, ...) {
+  va_list ap;
+  int ret;
+
+  va_start(ap, format);
+  ret = vsnprintf(buffer_data_remaining(buffer), buffer_size_remaining(buffer),
+                  format, ap);
+  if (ret > 0) {
+    if ((size_t)ret < buffer_size_remaining(buffer)) {
+      buffer_provide(buffer, ret);
+    } else {
+      buffer_provide(buffer, buffer_size_remaining(buffer));
+    }
+  }
+  va_end(ap);
+  return ret;
+}
+
+size_t buffer_size_remaining(const Buffer *buffer) {
   return buffer_capacity(buffer) - buffer_size(buffer);
 }
 

src/connection.c

@@ -1,5 +1,12 @@
+#include <sys/socket.h>
+#include <sys/types.h>
+
 #include <assert.h>
 #include <connection.h>
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <netdb.h>
 #include <unistd.h>
 
 #if INTERFACE
@@ -33,11 +40,69 @@ struct Connection {
 
 #endif
 
-void connection_init(EV_P_ Connection *connection, struct tls_config *config) {
+int connection_open(EV_P_ Connection *connection, struct tls_config *config,
+                    const char *servername, const char *serverport) {
+  struct addrinfo hints, *res, *res0;
+  int error, fd, tmp;
+  const char *cause;
+
   (void)(EV_A_ 0);
-  ev_io_init(&connection->watcher, NULL, STDIN_FILENO, 0);
+  memset(&hints, 0, sizeof(hints));
+  hints.ai_family = AF_UNSPEC;
+  hints.ai_socktype = SOCK_STREAM;
+  error = getaddrinfo(servername, serverport, &hints, &res0);
+  if (error) {
+    warnx("getaddrinfo: %s", gai_strerror(error));
+    goto err_getaddrinfo;
+  }
+  for (res = res0; res; res = res->ai_next) {
+    fd = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
+    if (fd == -1) {
+      cause = "socket";
+      continue;
+    }
+    if (connect(fd, res->ai_addr, res->ai_addrlen) == -1) {
+      tmp = errno;
+      close(fd);
+      errno = tmp;
+      cause = "connect";
+      continue;
+    }
+    break;
+  }
+  if (!fd) {
+    warn("%s", cause);
+    goto err_connect;
+  }
+  ev_io_init(&connection->watcher, NULL, fd, 0);
   connection->ctx = tls_client();
-  tls_configure(connection->ctx, config);
+  if (!connection->ctx) {
+    warnx("tls_client failed");
+    goto err_tls_client;
+  }
+  if (tls_configure(connection->ctx, config)) {
+    warnx("tls_configure: %s", tls_error(connection->ctx));
+    goto err_tls_configure;
+  }
+  if (tls_connect_socket(connection->ctx, fd, servername)) {
+    warnx("tls_connect: %s", tls_error(connection->ctx));
+    goto err_tls_connect_socket;
+  }
+  freeaddrinfo(res0);
+  return 0;
+
+err_tls_connect_socket:
+err_tls_configure:
+  tls_free(connection->ctx);
+
+err_tls_client:
+  close(fd);
+
+err_connect:
+  freeaddrinfo(res0);
+
+err_getaddrinfo:
+  return -1;
 }
 
 void connection_read_some(EV_P_ Connection *connection) {
@@ -61,6 +126,7 @@ static void connection_read_some_cb(EV_P_ ev_io *watcher, int revents) {
     ev_io_modify(watcher, EV_WRITE);
     ev_io_start(EV_A_ watcher);
   } else if (n == -1) {
+    warnx("tls_read: %s", tls_error(connection->ctx));
     connection->failure_cb(EV_A_ connection);
   } else {
     buffer_provide(&connection->read_buf, n);
@@ -89,6 +155,7 @@ static void connection_write_some_cb(EV_P_ ev_io *watcher, int revents) {
     ev_io_modify(watcher, EV_WRITE);
     ev_io_start(EV_A_ watcher);
   } else if (n == -1) {
+    warnx("tls_write: %s", tls_error(connection->ctx));
     connection->failure_cb(EV_A_ connection);
   } else {
     buffer_consume(&connection->write_buf, n);
@@ -96,8 +163,11 @@ static void connection_write_some_cb(EV_P_ ev_io *watcher, int revents) {
   }
 }
 
-void connection_stop(EV_P_ Connection *connection) {
+int connection_close(EV_P_ Connection *connection) {
+  int ret;
+
   ev_io_stop(EV_A_ & connection->watcher);
-  close(connection->watcher.fd);
+  ret = close(connection->watcher.fd);
   tls_free(connection->ctx);
+  return ret;
 }

src/http.c

@@ -0,0 +1,62 @@
+#include <http.h>
+#include <stdio.h>
+
+#if INTERFACE
+
+struct Http {
+  Connection connection;
+};
+
+#endif
+
+int http_get(EV_P_ Http *http, const char *servername, const char *path) {
+  struct tls_config *config;
+
+  config = tls_config_new();
+  if (connection_open(EV_DEFAULT_ & http->connection, config, servername,
+                      "https")) {
+    goto err_connection_open;
+  }
+  buffer_printf(connection_write_buf(&http->connection),
+                "GET %s HTTP/1.1\r\nHost: %s\r\nConnection: close\r\n\r\n",
+                path, servername);
+  connection_set_failure_cb(&http->connection, error_cb);
+  connection_set_cb(&http->connection, http_get_cb);
+  connection_write_some(EV_A_ & http->connection);
+  tls_config_free(config);
+  return 0;
+
+err_connection_open:
+  tls_config_free(config);
+  return -1;
+}
+
+static void error_cb(EV_P_ Connection *connection) {
+  connection_close(EV_A_ connection);
+  ev_break(EV_A_ EVBREAK_ALL);
+}
+
+static void http_get_cb(EV_P_ Connection *connection) {
+  if (buffer_size(connection_write_buf(connection))) {
+    connection_write_some(EV_A_ connection);
+    return;
+  }
+  connection_set_cb(connection, http_response_cb);
+  connection_read_some(EV_A_ connection);
+}
+
+static void http_response_cb(EV_P_ Connection *connection) {
+  Buffer *read_buf;
+  size_t n;
+
+  read_buf = connection_read_buf(connection);
+  n = buffer_size(read_buf);
+  if (n) {
+    fwrite(buffer_data(read_buf), n, 1, stdout);
+    buffer_consume(read_buf, n);
+    connection_read_some(EV_A_ connection);
+    return;
+  }
+  connection_close(EV_A_ connection);
+  ev_break(EV_A_ EVBREAK_ALL);
+}

src/main.c

@@ -3,14 +3,14 @@
 #include <tls.h>
 
 int main(int argc, char **argv) {
-  struct tls_config *config;
+  Http http;
-  Connection connection;
 
   (void)argc, (void)argv;
   tls_init();
-  config = tls_config_new();
+  if (http_get(EV_DEFAULT_ & http, "chat.heizhaus.org",
-  connection_init(EV_DEFAULT_ & connection, config);
+               "/.well-known/matrix/client")) {
-  tls_config_free(config);
+    return 1;
+  }
   ev_run(EV_DEFAULT_UC_ 0);
   return 0;
 }