/** Copy bytes from a buffer into a memory stream.
*
* @param data mem stream
* @param buf buffer
* @param n number of bytes to copy
*/
static void mem_put(MemData *data, const char *buf, size_t n){
char *start = mem_hi(data);
char *end = mem_end(data);
if(start + n < end){
memcpy(start, buf, n);
} else {
int k = end - start;
memcpy(start, buf, k);
memcpy(data->buf, buf + k, n - k);
}
}
/** Copy bytes from a memory stream into a buffer.
*
* @param data mem stream
* @param buf buffer
* @param n number of bytes to copy
*/
static void mem_get(MemData *data, char *buf, size_t n){
char *start = mem_lo(data);
char *end = mem_end(data);
if (start + n < end) {
memcpy(buf, start, n);
} else {
int k = end - start;
memcpy(buf, start, k);
memcpy(buf + k, data->buf, n - k);
}
}
bool process_next_command() {
char command[COMMAND_SIZE + 1];
int pid, address;
printf("\nrequest: > ");
fgets(command, sizeof command, stdin);
// process the entered command
if (sscanf(command, "begin p%d", &pid) == 1) {
mem_begin(pid);
} else if (sscanf(command, "read p%d %d", &pid, &address) == 2) {
mem_read(pid, address);
} else if (sscanf(command, "write p%d %d", &pid, &address) == 2) {
mem_write(pid, address);
} else if (sscanf(command, "end p%d", &pid) == 1) {
mem_end(pid);
} else if (strncmp(command, "view", 4) == 0) {
view_memory_system();
} else if (strncmp(command, "warnings", 8) == 0) {
if (messages) { printf(" sys !> warnings have been turned off\n"); }
else { printf(" sys !> warnings are on\n"); }
messages = !messages;
} else if (strncmp(command, "stop", 4) == 0) {
return false;
} else {
display_warning("main: unrecognized command");
}
return true;
}