source: mainline/uspace/lib/http/http.c@ ef2ecec

/*
 * Copyright (c) 2013 Martin Sucha
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup http
 * @{
 */
/**
 * @file
 */

#include <stdio.h>
#include <stdlib.h>
#include <str.h>
#include <macros.h>

#include <net/socket.h>
#include <inet/dnsr.h>

#include "http.h"

#define HTTP_METHOD_LINE "%s %s HTTP/1.1\r\n"
#define HTTP_HEADER_LINE "%s: %s\r\n"
#define HTTP_REQUEST_LINE "\r\n"

static char *cut_str(const char *start, const char *end)
{
        size_t size = end - start;
        return str_ndup(start, size);
}

static void recv_reset(http_t *http)
{
        http->recv_buffer_in = 0;
        http->recv_buffer_out = 0;
}

/** Receive one character (with buffering) */
static int recv_char(http_t *http, char *c, bool consume)
{
        if (http->recv_buffer_out == http->recv_buffer_in) {
                recv_reset(http);
                
                ssize_t rc = recv(http->conn_sd, http->recv_buffer, http->buffer_size, 0);
                if (rc <= 0)
                        return rc;
                
                http->recv_buffer_in = rc;
        }
        
        *c = http->recv_buffer[http->recv_buffer_out];
        if (consume)
                http->recv_buffer_out++;
        return EOK;
}

static ssize_t recv_buffer(http_t *http, char *buf, size_t buf_size)
{
        /* Flush any buffered data*/
        if (http->recv_buffer_out != http->recv_buffer_in) {
                size_t size = min(http->recv_buffer_in - http->recv_buffer_out, buf_size);
                memcpy(buf, http->recv_buffer + http->recv_buffer_out, size);
                http->recv_buffer_out += size;
                return size;
        }
        
        return recv(http->conn_sd, buf, buf_size, 0);
}

/** Receive a character and if it is c, discard it from input buffer */
static int recv_discard(http_t *http, char discard)
{
        char c = 0;
        int rc = recv_char(http, &c, false);
        if (rc != EOK)
                return rc;
        if (c != discard)
                return EOK;
        return recv_char(http, &c, true);
}

/* Receive a single line */
static ssize_t recv_line(http_t *http, char *line, size_t size)
{
        size_t written = 0;
        
        while (written < size) {
                char c = 0;
                int rc = recv_char(http, &c, true);
                if (rc != EOK)
                        return rc;
                if (c == '\n') {
                        recv_discard(http, '\r');
                        line[written++] = 0;
                        return written;
                }
                else if (c == '\r') {
                        recv_discard(http, '\n');
                        line[written++] = 0;
                        return written;
                }
                line[written++] = c;
        }
        
        return ELIMIT;
}

http_t *http_create(const char *host, uint16_t port)
{
        http_t *http = malloc(sizeof(http_t));
        if (http == NULL)
                return NULL;
        
        http->host = str_dup(host);
        if (http->host == NULL) {
                free(http);
                return NULL;
        }
        http->port = port;
        
        http->buffer_size = 4096;
        http->recv_buffer = malloc(http->buffer_size);
        if (http->recv_buffer == NULL) {
                free(http->host);
                free(http);
                return NULL;
        }
        
        return http;
}

int http_connect(http_t *http)
{
        if (http->connected)
                return EBUSY;
        
        /* Interpret as address */
        int rc = inet_addr_parse(http->host, &http->addr);
        
        if (rc != EOK) {
                /* Interpret as a host name */
                dnsr_hostinfo_t *hinfo = NULL;
                rc = dnsr_name2host(http->host, &hinfo, ip_any);
                
                if (rc != EOK)
                        return rc;
                
                http->addr = hinfo->addr;
                dnsr_hostinfo_destroy(hinfo);
        }
        
        struct sockaddr *saddr;
        socklen_t saddrlen;
        
        rc = inet_addr_sockaddr(&http->addr, http->port, &saddr, &saddrlen);
        if (rc != EOK) {
                assert(rc == ENOMEM);
                return ENOMEM;
        }
        
        http->conn_sd = socket(saddr->sa_family, SOCK_STREAM, 0);
        if (http->conn_sd < 0)
                return http->conn_sd;
        
        rc = connect(http->conn_sd, saddr, saddrlen);
        free(saddr);
        
        return rc;
}

http_header_t *http_header_create(const char *name, const char *value)
{
        char *dname = str_dup(name);
        if (dname == NULL)
                return NULL;
        
        char *dvalue = str_dup(value);
        if (dvalue == NULL) {
                free(dname);
                return NULL;
        }

        return http_header_create_no_copy(dname, dvalue);
}

http_header_t *http_header_create_no_copy(char *name, char *value)
{
        http_header_t *header = malloc(sizeof(http_header_t));
        if (header == NULL)
                return NULL;
        
        link_initialize(&header->link);
        header->name = name;
        header->value = value;
        
        return header;
}

void http_header_destroy(http_header_t *header)
{
        free(header->name);
        free(header->value);
        free(header);
}

http_request_t *http_request_create(const char *method, const char *path)
{
        http_request_t *req = malloc(sizeof(http_request_t));
        if (req == NULL)
                return NULL;
        
        req->method = str_dup(method);
        if (req->method == NULL) {
                free(req);
                return NULL;
        }
        
        req->path = str_dup(path);
        if (req->path == NULL) {
                free(req->method);
                free(req);
                return NULL;
        }
        
        list_initialize(&req->headers);
        
        return req;
}

void http_request_destroy(http_request_t *req)
{
        free(req->method);
        free(req->path);
        link_t *link = req->headers.head.next;
        while (link != &req->headers.head) {
                link_t *next = link->next;
                http_header_t *header = list_get_instance(link, http_header_t, link);
                http_header_destroy(header);
                link = next;
        }
        free(req);
}

static ssize_t http_encode_method(char *buf, size_t buf_size,
    const char *method, const char *path)
{
        if (buf == NULL) {
                return printf_size(HTTP_METHOD_LINE, method, path);
        }
        else {
                return snprintf(buf, buf_size, HTTP_METHOD_LINE, method, path);
        }
}

static ssize_t http_encode_header(char *buf, size_t buf_size,
    http_header_t *header)
{
        /* TODO properly split long header values */
        if (buf == NULL) {
                return printf_size(HTTP_HEADER_LINE, header->name, header->value);
        }
        else {
                return snprintf(buf, buf_size,
                    HTTP_HEADER_LINE, header->name, header->value);
        }
}

int http_request_format(http_request_t *req, char **out_buf,
    size_t *out_buf_size)
{
        /* Compute the size of the request */
        ssize_t meth_size = http_encode_method(NULL, 0, req->method, req->path);
        if (meth_size < 0)
                return meth_size;
        size_t size = meth_size;
        
        list_foreach(req->headers, link, http_header_t, header) {
                ssize_t header_size = http_encode_header(NULL, 0, header);
                if (header_size < 0)
                        return header_size;
                size += header_size;
        }
        size += str_length(HTTP_REQUEST_LINE);
        
        char *buf = malloc(size);
        if (buf == NULL)
                return ENOMEM;
        
        char *pos = buf;
        size_t pos_size = size;
        ssize_t written = http_encode_method(pos, pos_size, req->method, req->path);
        if (written < 0) {
                free(buf);
                return written;
        }
        pos += written;
        pos_size -= written;
        
        list_foreach(req->headers, link, http_header_t, header) {
                written = http_encode_header(pos, pos_size, header);
                if (written < 0) {
                        free(buf);
                        return written;
                }
                pos += written;
                pos_size -= written;
        }
        
        size_t rlsize = str_size(HTTP_REQUEST_LINE);
        memcpy(pos, HTTP_REQUEST_LINE, rlsize);
        pos_size -= rlsize;
        assert(pos_size == 0);
        
        *out_buf = buf;
        *out_buf_size = size;
        return EOK;
}

int http_send_request(http_t *http, http_request_t *req)
{
        char *buf;
        size_t buf_size;
        
        int rc = http_request_format(req, &buf, &buf_size);
        if (rc != EOK)
                return rc;
        
        rc = send(http->conn_sd, buf, buf_size, 0);
        free(buf);
        
        return rc;
}

int http_parse_status(const char *line, http_version_t *out_version,
    uint16_t *out_status, char **out_message)
{
        http_version_t version;
        uint16_t status;
        char *message = NULL;
        
        if (!str_test_prefix(line, "HTTP/"))
                return EINVAL;
        
        const char *pos_version = line + 5;
        const char *pos = pos_version;
        
        int rc = str_uint8_t(pos_version, &pos, 10, false, &version.major);
        if (rc != EOK)
                return rc;
        if (*pos != '.')
                return EINVAL;
        pos++;
        
        pos_version = pos;
        rc = str_uint8_t(pos_version, &pos, 10, false, &version.minor);
        if (rc != EOK)
                return rc;
        if (*pos != ' ')
                return EINVAL;
        pos++;
        
        const char *pos_status = pos;
        rc = str_uint16_t(pos_status, &pos, 10, false, &status);
        if (rc != EOK)
                return rc;
        if (*pos != ' ')
                return EINVAL;
        pos++;
        
        if (out_message) {
                message = str_dup(pos);
                if (message == NULL)
                        return ENOMEM;
        }
        
        if (out_version)
                *out_version = version;
        if (out_status)
                *out_status = status;
        if (out_message)
                *out_message = message;
        return EOK;
}

int http_parse_header(const char *line, char **out_name, char **out_value)
{
        const char *pos = line;
        while (*pos != 0 && *pos != ':') pos++;
        if (*pos != ':')
                return EINVAL;
        
        char *name = cut_str(line, pos);
        if (name == NULL)
                return ENOMEM;
        
        pos++;
        
        while (*pos == ' ') pos++;
        
        char *value = str_dup(pos);
        if (value == NULL) {
                free(name);
                return ENOMEM;
        }
        
        *out_name = name;
        *out_value = value;
        
        return EOK;
}

int http_receive_response(http_t *http, http_response_t **out_response)
{
        http_response_t *resp = malloc(sizeof(http_response_t));
        if (resp == NULL)
                return ENOMEM;
        memset(resp, 0, sizeof(http_response_t));
        list_initialize(&resp->headers);
        
        char *line = malloc(http->buffer_size);
        if (line == NULL) {
                free(resp);
                return ENOMEM;
        }
        
        int rc = recv_line(http, line, http->buffer_size);
        if (rc < 0)
                goto error;
        
        rc = http_parse_status(line, &resp->version, &resp->status,
            &resp->message);
        if (rc != EOK)
                goto error;
        
        while (true) {
                rc = recv_line(http, line, http->buffer_size);
                if (rc < 0)
                        goto error;
                if (*line == 0)
                        break;
                
                char *name = NULL;
                char *value = NULL;
                rc = http_parse_header(line, &name, &value);
                if (rc != EOK)
                        goto error;
                
                http_header_t *header = http_header_create_no_copy(name, value);
                if (header == NULL) {
                        free(name);
                        free(value);
                        rc = ENOMEM;
                        goto error;
                }
                
                list_append(&header->link, &resp->headers);
        }
        
        *out_response = resp;
        
        return EOK;
error:
        free(line);
        http_response_destroy(resp);
        return rc;
}

int http_receive_body(http_t *http, void *buf, size_t buf_size)
{
        return recv_buffer(http, buf, buf_size);
}

void http_response_destroy(http_response_t *resp)
{
        free(resp->message);
        link_t *link = resp->headers.head.next;
        while (link != &resp->headers.head) {
                link_t *next = link->next;
                http_header_t *header = list_get_instance(link, http_header_t, link);
                http_header_destroy(header);
                link = next;
        }
        free(resp);
}

int http_close(http_t *http)
{
        if (!http->connected)
                return EINVAL;
        
        return closesocket(http->conn_sd);
}

void http_destroy(http_t *http)
{
        free(http->recv_buffer);
        free(http);
}

/** @}
 */