cosmopolitan/tool/decode/lib/disassemblehex.c

61 lines
3.0 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ This program is free software; you can redistribute it and/or modify │
│ it under the terms of the GNU General Public License as published by │
│ the Free Software Foundation; version 2 of the License. │
│ │
│ This program is distributed in the hope that it will be useful, but │
│ WITHOUT ANY WARRANTY; without even the implied warranty of │
│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU │
│ General Public License for more details. │
│ │
│ You should have received a copy of the GNU General Public License │
│ along with this program; if not, write to the Free Software │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/stdio/stdio.h"
#include "libc/str/str.h"
#include "tool/decode/lib/disassemblehex.h"
static size_t countzeroes(const uint8_t *data, size_t size) {
size_t i;
for (i = 0; i < size; ++i) {
if (data[i] != '\0') break;
}
return i;
}
void disassemblehex(uint8_t *data, size_t size, FILE *f) {
int col;
uint8_t ch;
size_t i, z;
char16_t glyphs[kDisassembleHexColumns + 1];
col = 0;
for (i = 0; i < size; ++i) {
ch = data[i];
if (!col) {
z = countzeroes(&data[i], size - i) / kDisassembleHexColumns;
if (z > 2) {
fprintf(f, "\t.%s\t%zu*%d\n", "zero", z, kDisassembleHexColumns);
i += z * kDisassembleHexColumns;
if (i == size) break;
}
fprintf(f, "\t.%s\t", "byte");
memset(glyphs, 0, sizeof(glyphs));
}
/* TODO(jart): Fix Emacs */
glyphs[col] = kCp437[ch == '"' || ch == '\\' || ch == '#' ? '.' : ch];
if (col) fputc(',', f);
fprintf(f, "0x%02x", ch);
if (++col == kDisassembleHexColumns) {
col = 0;
fprintf(f, "\t#%hs\n", glyphs);
}
}
if (col) fputc('\n', f);
}