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#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <console.h>
#include <errno.h>
#include <syslinux/loadfile.h>
/* Macros */
#define ROWS_PER_PAGE 24
#define COLS_PER_ROW 16
#define BYTES_PER_PAGE (ROWS_PER_PAGE * COLS_PER_ROW)
/* Functions declarations */
static int usage(void);
static void eat_stdin(void);
static int do_page(void);
static void hexdump(const void *memory, size_t bytes);
/* Objects */
static const char *prog_name;
static int opt_page;
static int opt_no_buffer;
static int opt_extended_ascii;
int main(int argc, char **argv)
{
int rc;
const char *filename;
int i;
void *file_data;
size_t file_sz;
FILE *f;
size_t len;
const char *cur_pos;
/* Assume failure */
rc = EXIT_FAILURE;
/* Determine the program name, as invoked */
if (argc < 1 || !argv || !argv[0]) {
fprintf(stderr, "argc or argv failure!\n");
goto err_prog_name;
}
prog_name = argv[0];
/* Process arguments */
filename = NULL;
for (i = 1; i < argc; ++i) {
if (!argv[i]) {
fprintf(stderr, "argc and argv mismatch!\n");
goto err_argv;
}
if (!strncmp(argv[i], "--page", sizeof "--page") ||
!strncmp(argv[i], "-p", sizeof "-p")) {
opt_page = 1;
continue;
}
if (!strncmp(argv[i], "--no-buffer", sizeof "--no-buffer")) {
opt_no_buffer = 1;
continue;
}
if (!strncmp(argv[i], "--extended-ascii", sizeof "--extended-ascii")) {
opt_extended_ascii = 1;
continue;
}
if (!strncmp(argv[i], "--help", sizeof "--help") ||
!strncmp(argv[i], "-h", sizeof "-h") ||
!strncmp(argv[i], "-?", sizeof "-?"))
return usage();
/* Otherwise, interpret as a filename, but only accept one */
if (filename)
return usage();
filename = argv[i];
}
if (!filename)
return usage();
fprintf(stdout, "Dumping file: %s\n", filename);
/* Either fetch the whole file, or just allocate a buffer */
f = NULL;
if (opt_no_buffer) {
errno = 0;
if (loadfile(filename, &file_data, &file_sz)) {
fprintf(stderr, "Couldn't load file. Error: %d\n", errno);
goto err_file_data;
}
} else {
file_sz = BYTES_PER_PAGE;
file_data = malloc(file_sz);
if (!file_data) {
fprintf(stderr, "Couldn't allocate file data buffer\n");
goto err_file_data;
}
errno = 0;
f = fopen(filename, "r");
if (!f) {
fprintf(stderr, "Couldn't open file. Error: %d\n", errno);
goto err_f;
}
}
/* Dump the data */
len = BYTES_PER_PAGE;
cur_pos = file_data;
do {
if (f) {
/* Buffered */
len = fread(file_data, 1, file_sz, f);
cur_pos = file_data;
} else {
/* Non-buffered */
if (file_sz < len)
len = file_sz;
}
if (!len)
break;
hexdump(cur_pos, len);
/* Pause, if requested */
if (opt_page) {
/* The user might choose to quit */
if (do_page())
break;
}
/* Reduce file_sz for non-buffered mode */
if (!f)
file_sz -= len;
} while (cur_pos += len);
rc = EXIT_SUCCESS;
if (f)
fclose(f);
err_f:
free(file_data);
err_file_data:
err_argv:
err_prog_name:
return rc;
}
static int usage(void)
{
static const char usage[] =
"Usage: %s [<option> [...]] <filename> [<option> [...]]\n"
"\n"
"Options: -p\n"
" --page . . . . . . . Pause output every 24 lines\n"
" --no-buffer . . . . Load the entire file before dumping\n"
" --extended-ascii . . Use extended ASCII chars in dump\n"
" -?\n"
" -h\n"
" --help . . . . . . Display this help\n";
fprintf(stderr, usage, prog_name);
return EXIT_FAILURE;
}
static void eat_stdin(void)
{
int i;
while (1) {
i = fgetc(stdin);
if (i == EOF || i == '\n')
return;
}
}
static int do_page(void)
{
int i;
while (1) {
fprintf(stdout, "Continue? [Y|n]: ");
i = fgetc(stdin);
switch (i) {
case 'n':
case 'N':
eat_stdin();
return 1;
case EOF:
fprintf(stderr, "No response. Continuing...\n");
/* Fall through to "yes" */
case 'y':
case 'Y':
eat_stdin();
case '\n':
return 0;
default:
fprintf(stderr, "Invalid choice\n");
eat_stdin();
}
}
}
static void hexdump(const void *memory, size_t bytes)
{
const unsigned char *p, *q;
int i;
p = memory;
while (bytes) {
q = p;
printf("%p: ", (void *) p);
for (i = 0; i < 16 && bytes; ++i) {
printf("%02X ", *p);
++p;
--bytes;
}
bytes += i;
while (i < 16) {
printf("XX ");
++i;
}
printf("| ");
p = q;
for (i = 0; i < 16 && bytes; ++i) {
printf("%c", isprint(*p) && !isspace(*p) ? *p : ' ');
++p;
--bytes;
}
while (i < 16) {
printf(" ");
++i;
}
printf("\n");
}
return;
}
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