#include <sysexits.h>
#include <readline/readline.h>
-#include <readline/history.h>
#include "dcpu16.h"
}
}
+/* simplified strtoul with range checking */
static
-int file_load_(struct dcpu16 *vm, char *filename) {
+int str_to_word_(char *s) {
+ unsigned long l;
+ char *ep;
+
+ assert(s);
+
+ errno = 0;
+ l = strtoul(s, &ep, 0);
+
+ if (errno
+ || !(*s && *ep == '\0') ) {
+ /* out of range of conversion, or invalid character encountered */
+ return -1;
+ }
+
+ if (l >= DCPU16_RAM) {
+ /* out of range for our needs */
+ errno = ERANGE;
+ return -1;
+ }
+
+ return l;
+}
+
+/* clears the instance and loads an image into ram starting at addr */
+static
+int file_load_(struct dcpu16 *vm, char *filename, DCPU16_WORD addr) {
FILE *f;
size_t r;
+ assert(addr < DCPU16_RAM);
+
+ dcpu16_reset(vm);
+
f = fopen(filename, "rb");
if (f == NULL) {
fprintf(stderr, "%s('%s'):%s\n", "fopen", filename, strerror(errno));
return -1;
}
- r = fread(vm->ram, sizeof(DCPU16_WORD), DCPU16_RAM, f);
+ r = fread(vm->ram + addr, sizeof(DCPU16_WORD), DCPU16_RAM - addr, f);
VERBOSE_PRINTF("read %zu words", r);
+ if (addr) VERBOSE_PRINTF(" starting at 0x%04x", addr);
+ VERBOSE_PRINTF("\n");
if (ferror(f))
fprintf(stderr, "%s('%s'):%s\n", "fread", filename, strerror(errno));
return 0;
}
+/* the commands the vm shell can execute */
+
+struct command_ {
+ char *name;
+ int args_min;
+ int args_max;
+ int (*func)(struct dcpu16 *, int c, char **v);
+ void (*help)(FILE *f, unsigned int);
+};
+
+#define COMMAND_IMPL(x) static int command_##x##_(struct dcpu16 *vm, int token_count, char **token_vector)
+#define COMMAND_HELP(x) static void command_##x##_help_(FILE *f, unsigned int summary)
+#define COMMAND_ENTRY(x, y, z) { #x, y, z, command_##x##_, command_##x##_help_ }
+
+
+COMMAND_IMPL(quit) {
+ (void)vm, (void)token_count, (void)token_vector;
+ VERBOSE_PRINTF("done\n");
+ return -1;
+}
+COMMAND_HELP(quit) {
+ fprintf(f, "quit\n");
+ if (summary) return;
+
+ fprintf(f, "\tExits the emulator.\n");
+}
+
+
+COMMAND_IMPL(load) {
+ int addr = 0;
+
+ if (token_count > 1) {
+ addr = str_to_word_(token_vector[1]);
+ if (addr < 0) {
+ fprintf(stderr, "address '%s' is not a valid word: %s\n", token_vector[1], strerror(errno));
+ return 0;
+ }
+ }
+
+ if (file_load_(vm, token_vector[0], addr)) {
+ fprintf(stderr, "failed to load '%s'\n", token_vector[0]);
+ return 0;
+ }
+ printf("loaded '%s'", token_vector[0]);
+ if (addr) printf(" starting at 0x%04x", addr);
+ printf("\n");
+
+ return 0;
+}
+COMMAND_HELP(load) {
+ fprintf(f, "load file [addr]\n");
+ if (summary) return;
+
+ fprintf(f, "Usage: load file [addr]\n"
+ "\tAttempts to load binary image from 'file' at addr.\n");
+}
+
+
+COMMAND_IMPL(dump) {
+ int addr[2];
+ int i;
+
+ for (i = 0; i < token_count; i++) {
+ addr[i] = str_to_word_(token_vector[i]);
+ if (addr[i] < 0) {
+ fprintf(stderr, "address '%s' is not a valid word: %s\n", token_vector[i], strerror(errno));
+ return 0;
+ }
+ }
+ if (token_count < 1) addr[0] = vm->pc;
+ if (token_count < 2) addr[1] = addr[0];
+
+ if (addr[1] < addr[0]) {
+ fprintf(stderr, "\t'addr_start' must be before addr_end\n");
+ return 0;
+ }
+
+ dcpu16_dump_ram(vm, addr[0], addr[1]);
+
+ return 0;
+}
+COMMAND_HELP(dump) {
+ fprintf(f, "dump [addr_start [addr_end]]\n");
+ if (summary) return;
+
+ fprintf(f, "\tDisplays contents of ram from addr_start to addr_end.\n");
+}
+
+
+COMMAND_IMPL(disassemble) {
+ int addr[2];
+ int i;
+
+ for (i = 0; i < token_count; i++) {
+ addr[i] = str_to_word_(token_vector[i]);
+ if (addr[i] < 0) {
+ fprintf(stderr, "address '%s' is not a valid word: %s\n", token_vector[i], strerror(errno));
+ return 0;
+ }
+ }
+ if (token_count < 1) addr[0] = vm->pc;
+ if (token_count < 2) addr[1] = addr[0];
+
+ if (addr[1] < addr[0]) {
+ fprintf(stderr, "\t'addr_start' must be before addr_end\n");
+ return 0;
+ }
+
+ for (i = addr[0]; i <= addr[1]; i++)
+ dcpu16_disassemble_print(vm, i);
+
+ return 0;
+}
+COMMAND_HELP(disassemble) {
+ fprintf(f, "disassemble [addr_start [addr_end]]\n");
+ if (summary) return;
+
+ fprintf(f, "\tDisplays contents of ram parsed into instructions.\n");
+}
+
+
+COMMAND_IMPL(step) {
+ unsigned long count;
+ char *ep;
+
+ (void)token_count;
+
+ errno = 0;
+ count = strtoul(token_vector[0], &ep, 0);
+ if (errno
+ || !(*token_vector[0] && *ep == '\0') ) {
+ fprintf(stderr, "count '%s' is not a valid number: %s\n", token_vector[0], strerror(errno));
+ return 0;
+ }
+
+ if (count <= 0) {
+ fprintf(stderr, "count must be positive\n");
+ return 0;
+ }
+
+ while (count--) {
+ VERBOSE_PRINTF("executing next cycle, instruction: ");
+ dcpu16_disassemble_print(vm, vm->pc), printf("\n");
+
+ dcpu16_step(vm);
+
+ if (opt_.verbose)
+ dcpu16_state_print(vm);
+ }
+
+ return 0;
+}
+COMMAND_HELP(step) {
+ fprintf(f, "step [count]\n");
+ if (summary) return;
+
+ fprintf(f, "\tExecutes the next instruction, or the next count instructions.\n");
+}
+
+
+/* catch sigint while running, stop running */
+static volatile unsigned int running_ = 0;
+static
+void sigint_handler_(int sig) {
+ (void)sig;
+ running_ = 0;
+}
+COMMAND_IMPL(run) {
+ sig_t osig;
+ (void)token_count, (void)token_vector;
+
+ running_ = 1;
+
+ /* install our new interrupt signal handler */
+ if ( (osig = signal(SIGINT, sigint_handler_)) ) {
+ fprintf(stderr, "%s():%s\n", "signal", strerror(errno));
+ return -1;
+ }
+
+ while(running_) {
+ dcpu16_step(vm);
+ if (opt_.verbose)
+ dcpu16_state_print(vm);
+ }
+
+ /* restore the old interrupt signal handler */
+ if (signal(SIGINT, osig) == SIG_ERR) {
+ fprintf(stderr, "%s():%s\n", "sigaction", strerror(errno));
+ return -1;
+ }
+
+ VERBOSE_PRINTF("interrupted...\n");
+
+ return 0;
+}
+COMMAND_HELP(run) {
+ fprintf(f, "run\n");
+ if (summary) return;
+
+ fprintf(f, "\tBegins executing continuously.\n");
+}
+
+/* gather all these together into a searchable table */
+/* help command gets some assistance in declarations */
+COMMAND_IMPL(help);
+COMMAND_HELP(help);
+
+static struct command_ command_table_[] = {
+ COMMAND_ENTRY(help, 0, 1),
+ COMMAND_ENTRY(quit, 0, -1),
+ COMMAND_ENTRY(load, 1, 2),
+ COMMAND_ENTRY(dump, 0, 2),
+ COMMAND_ENTRY(disassemble, 0, 2),
+ COMMAND_ENTRY(step, 0, 1),
+ COMMAND_ENTRY(run, 0, 0),
+ { NULL, 0, 0, NULL, NULL }
+};
+
+COMMAND_IMPL(help) {
+ struct command_ *c;
+ (void)vm;
+
+ if (token_count) {
+ while (token_count) {
+ for (c = command_table_; c->func; c++) {
+ if (strcasecmp(*token_vector, c->name) == 0) {
+ if (c->help)
+ c->help(stdout, 0);
+ break;
+ }
+ }
+ token_count--;
+ token_vector++;
+ }
+ return 0;
+ }
+
+ for (c = command_table_; c->func; c++) {
+ if (c->help)
+ c->help(stdout, 1);
+ }
+ return 0;
+}
+COMMAND_HELP(help) {
+ if (summary) {
+ fprintf(f, "help [command]\n");
+ return;
+ }
+
+ fprintf(f, "Usage: help [command]\n"
+ "\tDisplays a list of available commands, or help on a specific command.\n");
+}
+
int main(int argc, char **argv) {
int c;
- char *command;
- char *prompt = "dcpu16> ";
+ char *line, *line_prev;
struct dcpu16 *vm;
+ char prompt[32];
+ const char prompt_fmt[] = "PC:%04x> ";
while ( (c = getopt(argc, argv, "hv")) != EOF) {
switch (c) {
}
if (argc) {
- file_load_(vm, *argv);
+ file_load_(vm, *argv, 0);
}
- dcpu16_state_print(vm);
- dcpu16_disassemble_print(vm, vm->pc);
- while ( (command = readline(prompt)) ) {
- if (strcasecmp(command, "quit") == 0)
+ /* show state, read commands */
+ for (line_prev = NULL,
+ snprintf(prompt, sizeof prompt, prompt_fmt, vm->pc),
+ dcpu16_state_print(vm);
+
+ (line = readline(prompt));
+
+ printf("\n"),
+ snprintf(prompt, sizeof prompt, prompt_fmt, vm->pc),
+ dcpu16_state_print(vm)) {
+ const char whitespace[] = " \t";
+ char *rest, *line_start, *command;
+ struct command_ *c;
+ int token_count;
+ char *token_vector[] = { NULL, NULL };
+ int r = 0;
+
+ /* skip whitespaces */
+ line_start = line + strspn(line, whitespace);
+
+ if (*line_start) {
+ /* a new command, it will be the prior command now */
+ free(line_prev);
+ line_prev = line;
+ } else {
+ /* empty command, read another line if there's no prior command to repeat */
+ if (line_prev == NULL || *line_prev == '\0') {
+ continue;
+ }
+
+ /* otherwise discard new line and repeat prior */
+ free(line);
+ line_start = line_prev + strspn(line, whitespace);
+ VERBOSE_PRINTF("repeating previous command '%s'\n", line_start);
+ }
+
+ /* first word */
+ command = strtok_r(line_start, whitespace, &rest);
+
+ /* look up command */
+ /* FIXME: tokenize 'rest' into proper argv */
+ token_count = 0;
+ if (rest)
+ token_count++, token_vector[0] = rest;
+ for (c = command_table_; c->name; c++) {
+ if (strcasecmp(command, c->name) == 0) {
+ if (c->args_min > token_count) {
+ fprintf(stderr, "%s: not enough arguments\n", c->name);
+ c->help(stderr, 1);
+ break;
+ }
+
+ if (c->args_max > 0
+ && token_count > c->args_max) {
+ fprintf(stderr, "%s: too many arguments\n", c->name);
+ c->help(stderr, 1);
+ break;
+ }
+
+ r = c->func(vm, token_count, token_vector);
+ break;
+ }
+ }
+ if (r)
break;
- dcpu16_step(vm);
- dcpu16_state_print(vm);
- dcpu16_disassemble_print(vm, vm->pc);
+ if (!c->func)
+ fprintf(stderr, "didn't recognize '%s'\n", command);
}
- printf("finished\n");
+ printf("\nfinished\n");
dcpu16_delete(&vm);
projects / dcpu16 / blobdiff