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#include <nserve.h>
int slurpsock(char *buf, size_t buf_sz, int sock)
{
ssize_t bytes;
bytes = recv(sock, buf, buf_sz, 0);
check(bytes >= 0, "Failed to read from socket: %d", sock);
return bytes;
error:
return -1;
}
int barfsock(char *buf, size_t buf_sz, int sock)
{
ssize_t bytes = 0;
bytes = send(sock, buf, buf_sz, 0);
check(bytes >= 0, "barfsock: send failed");
return bytes;
error:
return -1;
}
int check_cmd_size(char *cmd, int sock)
{
check(cmd != NULL, "cmd is NULL");
size_t len = strlen(cmd);
if (len <= CMD_SIZE) {
return 0;
}
char *err = "error: command invalid: size > 120 characters\n";
ssize_t err_sz = strlen(err);
ssize_t bytes = send(sock, err, err_sz, 0);
check(bytes == err_sz, "check_cmd_size: send failed");
return 1;
error:
return -1;
}
void nserve(int sock)
{
size_t cmd_sz = 200;
char *cmd = calloc(sizeof(char), cmd_sz);
check_mem(cmd);
// Read command from socket.
ssize_t bytes = slurpsock(cmd, cmd_sz, sock);
check(bytes >= 0, "nserve: slurpsock failed");
int rc = check_cmd_size(cmd, sock);
check(rc != -1, "command size check failed");
// Quit immediately if cmd size is too large.
if (rc == 1) {
goto error;
}
// Write response to socket.
rc = barfsock(cmd, bytes, sock);
check(rc != -1, "nserve: echo failed");
// Close socket.
rc = close(sock);
check(rc == 0, "nserve: close failed");
// Cleanup.
free(cmd);
exit(0);
error:
rc = close(sock);
check(rc == 0, "nserve: close failed");
// Cleanup if needed.
if (cmd)
free(cmd);
exit(1);
}
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