src/http/request_parser.c

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#include <stdlib.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <ctype.h>
#include <sys/types.h>

#include "class.h"
#include "http/request_parser.h"
#include "interface/class.h"
#include "interface/stream_reader.h"
#include "http/request.h"
#include "http/request_queue.h"

static
void
httpRequestParserParse(HttpRequestParser);

static
void
ctor(void * _this, va_list * params)
{
        HttpRequestParser this = _this;

        this->request_queue = new(HttpRequestQueue);

        this->buffer = malloc(HTTP_REQUEST_PARSER_READ_CHUNK);
        this->buffer[0] = 0;
}

static
void
dtor(void * _this)
{
        HttpRequestParser this = _this;

        free(this->buffer);
        delete(&(this->request_queue));
} 

static
void
_clone(void * _this, void * _base)
{
        HttpRequestParser this = _this;
        HttpRequestParser base = _base;
        size_t            chunks;

        this->request_queue = new(HttpRequestQueue);
        this->buffer_used   = base->buffer_used;

        chunks = this->buffer_used / HTTP_REQUEST_PARSER_READ_CHUNK;
        chunks++;

        this->buffer = malloc(chunks * HTTP_REQUEST_PARSER_READ_CHUNK);
        memcpy(this->buffer, base->buffer, this->buffer_used);
}

static
size_t
get_data(void * _this, int fd)
{
        HttpRequestParser this = _this;
        size_t            remaining, chunks;
        char              buffer[1024];

        size_t size = read(fd, buffer, 1024);

        if (0 < size) {
                remaining = this->buffer_used % HTTP_REQUEST_PARSER_READ_CHUNK;
                chunks    = this->buffer_used / HTTP_REQUEST_PARSER_READ_CHUNK;

                chunks++;

                if (size >= remaining) {
                        this->buffer =
                                realloc(this->buffer, chunks * HTTP_REQUEST_PARSER_READ_CHUNK);
                }

                memcpy(this->buffer + this->buffer_used, buffer, size);
                this->buffer_used += size;
                this->buffer[this->buffer_used] = 0;

                httpRequestParserParse(this);
        }

        return size;
}

INIT_IFACE(Class, ctor, dtor, _clone);
INIT_IFACE(StreamReader, get_data);
CREATE_CLASS(HttpRequestParser, NULL, IFACE(Class), IFACE(StreamReader));

static
inline
char *
httpRequestLineGet(char ** data)
{
        char * line_end = strstr(*data, "\r\n");
        char * ret      = *data;

        if (NULL == line_end) {
                return NULL;
        }

        *line_end = 0;
        *data = line_end + 2;

        return ret;
}

static
inline
void
httpRequestSkip(char ** data)
{
        for (; 0 != **data && ! isalpha(**data); (*data)++);
}

static
void
httpRequestParserParse(HttpRequestParser this)
{
        static HttpRequest request  = NULL;
        static char *      data; // static pointer to unprocessed data
        char *             line;
        int                cont = 1;
        static int         header_idx;

        while(cont) {
                switch(this->state) {
                        case HTTP_REQUEST_GARBAGE:
                                data = this->buffer; // initialize static pointer
                                httpRequestSkip(&data);
                                request = new(HttpRequest);

                                this->state = HTTP_REQUEST_START;
                                break;

                        case HTTP_REQUEST_START:
                                if (NULL == (line = httpRequestLineGet(&data))) {
                                        cont = 0;
                                        break;
                                }
                                
                                {
                                        char * delim = strchr(line, ' ');

                                        if (NULL != delim) {
                                                *delim = 0;
                                                request->method = malloc(strlen(line) + 1);
                                                strcpy(request->method, line);
                                                line = delim + 1;

                                                for (; *line == ' ' && *line != 0; line++);

                                                if (0 != *line) {
                                                        delim = strchr(line, ' ');

                                                        if (NULL != delim) {
                                                                *delim = 0;
                                                                request->uri = malloc(strlen(line) + 1);
                                                                strcpy(request->uri, line);
                                                                line = delim + 1;

                                                                for (; *line == ' ' && *line != 0; line++);

                                                                if (0 != *line) {
                                                                        request->http_version = malloc(strlen(line) + 1);
                                                                        strcpy(request->http_version, line);
                                                                }
                                                        }
                                                }
                                        }
                                }

                                header_idx = 0;
                                this->state = HTTP_REQUEST_REQUEST_LINE_DONE;
                                break;

                        case HTTP_REQUEST_REQUEST_LINE_DONE:
                                if (NULL == (line = httpRequestLineGet(&data))) {
                                        cont = 0;
                                        break;
                                }

                                if (0 == strlen(line)) {
                                        this->state = HTTP_REQUEST_HEADERS_DONE;
                                        break;
                                }

                                {
                                        char * delim = strchr(line, ':');

                                        *delim = 0;
                                        (request->header)[header_idx].name = malloc(strlen(line) + 1);
                                        strcpy((request->header)[header_idx].name, line);

                                        line = delim + 1;
                                        for (; *line == ' ' && *line != 0; line++);

                                        (request->header)[header_idx].value = malloc(strlen(line) + 1);
                                        strcpy((request->header)[header_idx].value, line);
                                }

                                header_idx++;
                                break;

                        case HTTP_REQUEST_HEADERS_DONE:
                                this->state = HTTP_REQUEST_DONE;
                                break;

                        case HTTP_REQUEST_DONE:
                                this->request_queue->requests[(this->request_queue->nrequests)++] =
                                        request;

                                memmove(this->buffer,
                                                data,
                                                this->buffer_used - (data - this->buffer) + 1);

                                this->buffer_used -= data - this->buffer;

                                if (0 == this->buffer_used) {
                                        cont = 0;
                                }

                                this->state = HTTP_REQUEST_GARBAGE;

                                break;

                        default:
                                break;
                }
        }
}

// vim: set ts=4 sw=4: