Unexpected behavior when reading from socket

I've wrote the following function that reads http response from the server through the socket. I had no problems reading text pages like this page but when I try to read images:

the reading goes on without adding data to the buffer, even though the read returns the correct byte amount.

The function:

unsigned char *read_unknown_size(int fd) {
    int available_buf_size = 1000, tot_read = 0, curr_read_size;
    unsigned char *buf = calloc(available_buf_size, 1), *tmp_ptr;
    if (buf) {
        while ((curr_read_size = (int) read(fd, buf + tot_read, available_buf_size - tot_read)) != 0) {
            if (curr_read_size == -1) {
                perror("failed to read\n");
                //todo free mem
                exit(EXIT_FAILURE);
            } else {
                tot_read += curr_read_size;
                if (tot_read >= available_buf_size) { //the buffer is full
                    available_buf_size *= 2;
                    tmp_ptr = realloc(buf, available_buf_size + tot_read);
                    if (tmp_ptr) {
                        buf = tmp_ptr;
                        memset(buf+tot_read, 0, available_buf_size - tot_read);
                    }
                    else {
                        fprintf(stderr,"realloc failed\n");
                        exit(EXIT_FAILURE);
                    }
                }
            }
        }
    } else {
        fprintf(stderr,"calloc failed\n");
        exit(EXIT_FAILURE);
    }
    return buf;
}

The buffer after one reading of size 1000:

0x563a819da130 "HTTP/1.1 200 OK\r\nDate: Tue, 23 Nov 2021 19:32:01 GMT\r\nServer: Apache\r\nUpgrade: h2,h2c\r\nConnection: Upgrade, close\r\nLast-Modified: Sat, 11 Jan 2014 01:32:55 GMT\r\nAccept-Ranges: bytes\r\nContent-Length: 3900\r\nCache-Control: max-age=2592000\r\nExpires: Thu, 23 Dec 2021 19:32:01 GMT\r\nContent-Type: image/jpeg\r\n\r\nGIF89", <incomplete sequence \375>

A total of 379 character.

Edit: After reading the data, I'm writing it to a new file, the text pages works fine but I can't open images.

from Recent Questions - Stack Overflow https://ift.tt/3l02ajl
https://ift.tt/3CSRN7q