Thread: Sending png to browser

I'm trying to do a small web server. I want this server to send a png.

The client browser sends the request:

Code:

GET /someimage.png HTTP/1.1

loads of information I don't care about

The server receives and understands the request, however I can't send a png with success.

I'm doing it like this:

Code:

    char * buf= calloc(FILE_BUF_SIZE + 40, sizeof(char));
    int fd;
    char file[FILE_BUF_SIZE];
    char * filetype;

    bzero(&file, FILE_BUF_SIZE);

    filetype= file_type(file_addr);



    fd= open(file_addr, O_RDONLY);

    if(fd < 0)
        perror("error opening file");

    if(read(fd, file, FILE_BUF_SIZE) < 0)
        perror("error reading file");

    close(fd);


    sprintf(buf, "Content-Type: %s\n\n%s", filetype, file);

Then some other function adds "HTTP/1.1 200 OK" and the final message should look like:

Code:

HTTP/1.1 200 OK
Content-Type: image/png

png file completely raw
\r\n

Errors I might think I might have:

1- I don't know if the \r\n should go on another message

2- The png might need to be processed before sending it to the client browser

With this same code applied to html files I was able to send and present it correctly on the browser

Also the FILE_BUF_SIZE is currently set as 10k. The png I am trying to send is 3.5k, so there should be no problem there

This is the function that sends the message to the client:

Code:

void send_file(int remotefd, char file_addr[], int http_subver){

    char *file;
    char buf[FILE_BUF_SIZE + 60];

    bzero(buf, FILE_BUF_SIZE + 60);

    file= read_file(file_addr);

    sprintf(buf, "HTTP/1.%d 200 OK\n", http_subver);

    strncat(buf, file, FILE_BUF_SIZE+40);

    free(file);

    write(remotefd, buf, strlen(buf));

    printf("%s", buf);

    return;
}

This is the sub function that builds the message:

Code:

#define FILE_BUF_SIZE 1024*10 //10k
#define SEND_FILE "Content-Type: %s\n\n%s\n\r\n"


char * read_file(char * file_addr){

    char * buf= calloc(FILE_BUF_SIZE + 40, sizeof(char));
    int fd;
    char file[FILE_BUF_SIZE];
    char * filetype;


    bzero(&file, FILE_BUF_SIZE);

    filetype= file_type(file_addr);



    fd= open(file_addr, O_RDONLY);

    if(fd < 0)
        perror("error opening file");

    if(read(fd, file, FILE_BUF_SIZE) < 0)
        perror("error reading file");

    close(fd);


    sprintf(buf, SEND_FILE, filetype, file);



    return buf;
}