2025-03-13 11:32:41 +01:00

525 lines
14 KiB
C

#include "http_server.h"
#include "http_server_internal.h"
#include "str_util.h"
#include <ctype.h>
#include <netinet/in.h>
#include <pthread.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <threads.h>
#include <unistd.h>
HttpServer* http_server_new(HttpServerOpts opts)
{
int server_fd = socket(AF_INET, SOCK_STREAM, 0);
if (server_fd == -1) {
fprintf(stderr, "error: could not initialize socket\n");
return NULL;
}
SockAddrIn server_addr;
server_addr.sin_family = AF_INET;
server_addr.sin_addr.s_addr = INADDR_ANY;
server_addr.sin_port = htons(opts.port);
int reuse = 1;
setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse));
int res = bind(server_fd, (SockAddr*)&server_addr, sizeof(server_addr));
if (res != 0) {
fprintf(stderr, "error: could not bind socket\n");
return NULL;
}
res = listen(server_fd, 16);
if (res != 0) {
fprintf(stderr, "error: could not listen on socket\n");
return NULL;
}
HttpServer* server = malloc(sizeof(HttpServer));
*server = (HttpServer) {
.file = server_fd,
.addr = server_addr,
// .ctx = {},
.workers = malloc(sizeof(Worker) * opts.workers_amount),
.workers_size = opts.workers_amount,
.handlers = { 0 },
.not_found_handler = NULL,
.user_ctx = NULL,
};
ctx_construct(&server->ctx, server);
for (size_t i = 0; i < opts.workers_amount; ++i) {
worker_construct(&server->workers[i], &server->ctx);
}
handler_vec_construct(&server->handlers);
return server;
}
void http_server_free(HttpServer* server)
{
close(server->file);
for (size_t i = 0; i < server->workers_size; ++i) {
worker_destroy(&server->workers[i]);
}
ctx_destroy(&server->ctx);
handler_vec_destroy(&server->handlers);
free(server);
}
int http_server_listen(HttpServer* server)
{
Cx* ctx = &server->ctx;
while (true) {
SockAddrIn client_addr;
socklen_t addr_size = sizeof(client_addr);
int res = accept(server->file, (SockAddr*)&client_addr, &addr_size);
if (res == -1) {
fprintf(stderr, "error: could not accept\n");
return -1;
}
Client req = { .file = res, client_addr };
pthread_mutex_lock(&ctx->mutex);
res = request_queue_push(&ctx->req_queue, req);
if (res != 0) {
fprintf(stderr, "error: request queue full\n");
return -1;
}
pthread_mutex_unlock(&ctx->mutex);
pthread_cond_signal(&ctx->cond);
}
}
void http_server_set_user_ctx(HttpServer* server, void* user_ctx)
{
server->user_ctx = user_ctx;
}
void http_server_get(
HttpServer* server, const char* path, HttpHandlerFn handler)
{
handler_vec_push(
&server->handlers, (Handler) { path, .method = Method_GET, handler });
}
void http_server_post(
HttpServer* server, const char* path, HttpHandlerFn handler)
{
handler_vec_push(
&server->handlers, (Handler) { path, .method = Method_POST, handler });
}
void http_server_set_not_found(HttpServer* server, HttpHandlerFn handler)
{
server->not_found_handler = handler;
}
void* http_ctx_user_ctx(HttpCtx* ctx)
{
return ctx->user_ctx;
}
const char* http_ctx_req_path(HttpCtx* ctx)
{
return ctx->req->path;
}
bool http_ctx_req_headers_has(HttpCtx* ctx, const char* key)
{
return req_has_header(ctx->req, key);
}
const char* http_ctx_req_headers_get(HttpCtx* ctx, const char* key)
{
return req_get_header(ctx->req, key);
}
const char* http_ctx_req_body(HttpCtx* ctx)
{
return ctx->req_body;
}
void http_ctx_res_headers_set(HttpCtx* ctx, const char* key, const char* value)
{
char* key_copy = malloc(strlen(key) + 1);
strcpy(key_copy, key);
char* value_copy = malloc(strlen(value) + 1);
strcpy(value_copy, value);
header_vec_push(&ctx->res_headers, (Header) { key_copy, value_copy });
}
void http_ctx_respond(HttpCtx* ctx, int status, const char* body)
{
// https://httpwg.org/specs/rfc9112.html#persistent.tear-down
http_ctx_res_headers_set(ctx, "Connection", "close");
String res;
string_construct(&res);
char first_line[32];
snprintf(first_line, 32 - 1, "HTTP/1.1 %d %s\r\n", status,
http_response_code_string(status));
string_push_str(&res, first_line);
for (size_t i = 0; i < ctx->res_headers.size; ++i) {
Header* header = &ctx->res_headers.data[i];
char line[96];
snprintf(line, 96 - 1, "%s: %s\r\n", header->key, header->value);
string_push_str(&res, line);
}
string_push_str(&res, "\r\n");
string_push_str(&res, body);
ssize_t bytes_written = write(ctx->client->file, res.data, res.size);
if (bytes_written != (ssize_t)res.size) {
fprintf(stderr, "error: could not send response\n");
}
string_destroy(&res);
}
//
//
//
static inline void ctx_construct(Cx* ctx, const HttpServer* server)
{
ctx->server = server;
pthread_mutex_init(&ctx->mutex, NULL);
pthread_cond_init(&ctx->cond, NULL);
request_queue_construct(&ctx->req_queue, 8192);
}
static inline void ctx_destroy(Cx* ctx)
{
pthread_mutex_destroy(&ctx->mutex);
pthread_cond_destroy(&ctx->cond);
request_queue_destroy(&ctx->req_queue);
}
static inline int worker_construct(Worker* worker, Cx* ctx)
{
*worker = (Worker) {
// .thread = {},
.ctx = ctx,
};
pthread_create(&worker->thread, NULL, worker_thread_fn, worker);
return 0;
}
static inline void worker_destroy(Worker* worker)
{
if (worker->thread != 0) {
pthread_cancel(worker->thread);
// a bit ugly, but who cares?
pthread_cond_broadcast(&worker->ctx->cond);
pthread_join(worker->thread, NULL);
}
}
static inline void* worker_thread_fn(void* data)
{
Worker* worker = data;
worker_listen(worker);
return NULL;
}
static inline void worker_listen(Worker* worker)
{
Cx* ctx = worker->ctx;
while (true) {
pthread_testcancel();
pthread_mutex_lock(&ctx->mutex);
if (request_queue_size(&ctx->req_queue) > 0) {
Client req;
request_queue_pop(&ctx->req_queue, &req);
pthread_mutex_unlock(&ctx->mutex);
worker_handle_request(worker, &req);
continue;
}
pthread_cond_wait(&ctx->cond, &ctx->mutex);
pthread_mutex_unlock(&ctx->mutex);
}
}
static inline void worker_handle_request(Worker* worker, Client* client)
{
(void)worker;
uint8_t* buffer = calloc(MAX_HEADER_BUFFER_SIZE, sizeof(char));
ssize_t bytes_received = recv(client->file, buffer, MAX_HEADER_BUFFER_SIZE * sizeof(char), 0);
if (bytes_received == -1) {
fprintf(stderr, "error: could not receive request\n");
goto l0_return;
}
size_t header_end = 0;
for (ssize_t i = 0; i < bytes_received - 3; ++i) {
if (memcmp((char*)&buffer[i], "\r\n\r\n", 4)) {
header_end = (size_t)i + 5;
}
}
if (header_end == 0) {
fprintf(stderr, "error: header too big, exceeded %d bytes\n",
MAX_HEADER_BUFFER_SIZE);
goto l0_return;
}
Req req;
size_t body_idx;
int res = parse_header(&req, &body_idx, (char*)buffer, header_end);
if (res != 0) {
fprintf(stderr, "error: failed to parse header\n");
goto l0_return;
}
char* body = NULL;
if (req.method == Method_POST) {
if (!req_has_header(&req, "Content-Length")) {
fprintf(stderr,
"error: POST request has no body and/or Content-Length "
"header\n");
goto l1_return;
}
const char* length_val = req_get_header(&req, "Content-Length");
size_t length = strtoul(length_val, NULL, 10);
body = calloc(length + 1, sizeof(char));
strncpy(body, (char*)&buffer[body_idx], length);
body[length] = '\0';
// HACK
// TODO: We should treat the input as a stream rather than a block.
// Look at either @camper0008's stream example or other HTTP-server implementations.
size_t defacto_length = strlen(body);
int attempts = 0;
const int arbitrary_max_attempts = 10;
while (defacto_length < length && attempts < arbitrary_max_attempts) {
attempts += 1;
uint8_t buffer[8192];
ssize_t recieved = recv(client->file, buffer, 8192, 0);
if (recieved == -1) {
fprintf(stderr, "error: could not receive request body\n");
goto l1_return;
}
strncpy(&body[defacto_length], (char*)buffer, (size_t)recieved);
defacto_length += (size_t)recieved;
body[defacto_length] = '\0';
}
if (defacto_length < length) {
fprintf(stderr, "error: could not receive entire request body\n");
goto l1_return;
}
}
HttpCtx handler_ctx = {
.client = client,
.req = &req,
.req_body = body,
.res_headers = { 0 },
.user_ctx = worker->ctx->server->user_ctx,
};
header_vec_construct(&handler_ctx.res_headers);
bool been_handled = false;
for (size_t i = 0; i < worker->ctx->server->handlers.size; ++i) {
Handler* handler = &worker->ctx->server->handlers.data[i];
if (handler->method != req.method)
continue;
if (strcmp(handler->path, req.path) != 0)
continue;
handler->handler(&handler_ctx);
been_handled = true;
break;
}
if (!been_handled && worker->ctx->server->not_found_handler != NULL) {
worker->ctx->server->not_found_handler(&handler_ctx);
}
l1_return:
header_vec_destroy(&handler_ctx.res_headers);
req_destroy(&req);
if (body)
free(body);
l0_return:
free(buffer);
close(client->file);
}
static inline int parse_header(
Req* req, size_t* body_idx, const char* const buf, size_t buf_size)
{
StrSplitter splitter = str_split(buf, buf_size, "\r\n");
StrSlice req_line = strsplit_next(&splitter);
StrSplitter req_line_splitter = str_split(req_line.ptr, req_line.len, " ");
StrSlice method_str = strsplit_next(&req_line_splitter);
StrSlice uri_str = strsplit_next(&req_line_splitter);
StrSlice version_str = strsplit_next(&req_line_splitter);
if (strncmp(version_str.ptr, "HTTP/1.1", 8) != 0) {
fprintf(stderr, "error: unrecognized http version '%.*s'\n",
(int)version_str.len, version_str.ptr);
return -1;
}
if (method_str.len >= 8) {
fprintf(stderr, "error: malformed http method\n");
return -1;
}
char normalized_method[8] = "";
for (size_t i = 0; i < method_str.len; ++i) {
normalized_method[i] = (char)toupper(method_str.ptr[i]);
}
Method method;
if (strncmp(normalized_method, "GET", method_str.len) == 0) {
method = Method_GET;
} else if (strncmp(normalized_method, "POST", method_str.len) == 0) {
method = Method_POST;
} else {
fprintf(stderr, "error: unrecognized http method '%.*s'\n",
(int)method_str.len, method_str.ptr);
return -1;
}
if (uri_str.len >= MAX_PATH_LEN + 1) {
fprintf(stderr, "error: path too long\n");
return -1;
}
size_t path_len = 0;
while (path_len < uri_str.len && uri_str.ptr[path_len] != '?'
&& uri_str.ptr[path_len] != '#') {
path_len += 1;
}
char* path = calloc(path_len + 1, sizeof(char));
strncpy(path, uri_str.ptr, path_len);
path[path_len] = '\0';
char* query = NULL;
if (path_len < uri_str.len) {
size_t query_len = 0;
while (path_len + query_len < uri_str.len
&& uri_str.ptr[path_len + query_len] != '#') {
query_len += 1;
}
query = calloc(query_len + 1, sizeof(char));
strncpy(query, &uri_str.ptr[path_len], query_len);
query[query_len] = '\0';
}
HeaderVec headers;
header_vec_construct(&headers);
while (headers.size < MAX_HEADERS_LEN) {
StrSlice line = strsplit_next(&splitter);
if (line.len == 0) {
*body_idx = (size_t)&line.ptr[2] - (size_t)buf;
break;
}
size_t key_len = 0;
while (key_len < line.len && line.ptr[key_len] != ':') {
key_len += 1;
}
if (key_len == 0 || key_len > MAX_HEADER_KEY_LEN) {
fprintf(stderr, "error: header key too long\n");
return -1;
}
size_t value_begin = key_len + 1;
while (value_begin < line.len && line.ptr[value_begin] == ' ') {
value_begin += 1;
}
size_t value_len = line.len - value_begin;
if (value_len == 0 || value_len > MAX_HEADER_VALUE_LEN) {
fprintf(stderr, "error: header value too long, %ld\n", value_len);
return -1;
}
char* key = calloc(key_len + 1, sizeof(char));
strncpy(key, line.ptr, key_len);
char* value = calloc(value_len + 1, sizeof(char));
strncpy(value, &line.ptr[value_begin], value_len);
header_vec_push(&headers, (Header) { key, value });
}
*req = (Req) { method, path, query, headers };
return 0;
}
static inline void req_destroy(Req* req)
{
free(req->path);
for (size_t i = 0; i < req->headers.size; ++i) {
free(req->headers.data[i].key);
free(req->headers.data[i].value);
}
header_vec_destroy(&req->headers);
}
static inline int strcmp_lower(const char* a, const char* b)
{
size_t i = 0;
for (; a[i] != '\0' && b[i] != '\0'; ++i) {
if (tolower(a[i]) != tolower(b[i])) {
return 1;
}
}
if (a[i] != b[i]) {
return 1;
}
return 0;
}
static inline bool req_has_header(const Req* req, const char* key)
{
for (size_t i = 0; i < req->headers.size; ++i) {
if (strcmp_lower(key, req->headers.data[i].key) == 0) {
return true;
}
}
return false;
}
static inline const char* req_get_header(const Req* req, const char* key)
{
for (size_t i = 0; i < req->headers.size; ++i) {
if (strcmp_lower(key, req->headers.data[i].key) == 0) {
return req->headers.data[i].value;
}
}
return NULL;
}