// Read a simulator command from the keyboard ("h", "?", "d", number,
// or empty line) and execute it. Return true if we hit end-of-input
// or execute_command told us to quit. Otherwise return false.
//
int read_execute_command(int reg[], int nreg, int mem[], int memlen) {
// Buffer for the command line from the keyboard, plus its size
//
char *cmd_buffer = NULL;
size_t cmd_buffer_len = 0, bytes_read = 0;
// Values read using sscanf of command line
//
int nbr_cycles;
char cmd_char;
size_t words_read; // number of items read by sscanf call
int done = 0; // Should simulator stop?
bytes_read = getline(&cmd_buffer, &cmd_buffer_len, stdin);
if (bytes_read == -1) {
done = 1; // Hit end of file
}
words_read = sscanf(cmd_buffer, "%d", &nbr_cycles);
// If we found a number, do that many instruction cycles.
// Otherwise sscanf for a character and call execute_command with it.
// (Note the character might be '\n'.)
//
// printf("%d %d",words_read,nbr_cycles);
if (words_read == 1) {
many_instruction_cycles(nbr_cycles,reg,nreg,mem,memlen);
} else {
words_read = sscanf(cmd_buffer,"%c",&cmd_char);
execute_command(cmd_char,reg,nreg,mem,memlen);
}
free(cmd_buffer);
return done;
}
int read_execute_command(CPU *cpu) {
// Buffer to read next command line into
#define CMD_LINE_LEN 80
char cmd_line[CMD_LINE_LEN];
char *read_success; // NULL if reading in a line fails.
int nbr_cycles; // Number of instruction cycles to execute
char cmd_char; // Command 'q', 'h', '?', 'd', or '\n'
int done = 0; // Should simulator stop?
int words_read;
read_success = fgets(cmd_line, CMD_LINE_LEN, stdin);
while (read_success != NULL && !done) {
words_read = sscanf(cmd_line, "%d", &nbr_cycles);
if (words_read==1){
many_instruction_cycles(nbr_cycles, cpu);
} else {
words_read = sscanf(cmd_line,"%c",&cmd_char);
execute_command(cmd_char, cpu);
}
read_success = fgets(cmd_line, CMD_LINE_LEN, stdin);
}
return done;
}
int read_execute_command(int reg[], int nreg, int mem[], int memlen)
{
char *cmd_buffer = NULL;
size_t cmd_buffer_len = 0, bytes_read = 0;
int nbr_cycles;
char cmd_char;
size_t words_read;
int done = 0;
/* Get user input */
bytes_read = getline(&cmd_buffer, &cmd_buffer_len, stdin);
/* Did we hit the end of file? */
if (bytes_read == -1) {
done = 1;
}
words_read = sscanf(cmd_buffer, "%d", &nbr_cycles);
/* If a char was read then try to execute the according
* command, else if an integer was entered, try to
* execute this number of cycles */
if (words_read == 0) {
sscanf(cmd_buffer, "%c", &cmd_char);
done = execute_command(cmd_char, reg, nreg, mem, memlen);
} else {
/* Check first is the number of cycles is invalid.
* If yes then execute one or more instructions */
if (nbr_cycles < 1 ||
nbr_cycles > memlen ||
nbr_cycles > (memlen - pc)) {
printf("%d is an invalid number of cycles!!", nbr_cycles);
} else if (nbr_cycles == 1) {
one_instruction_cycle(reg, nreg, mem, memlen);
} else {
many_instruction_cycles(nbr_cycles, reg, nreg, mem, memlen);
}
}
/* Command buffer not needed anymore */
free(cmd_buffer);
return done;
}