diff Meerwald-dir/signature-utils.c @ 24:9f20bce6184e v0.7

move directories, support netpbm 11
author Peter Meerwald-Stadler <pmeerw@pmeerw.net>
date Fri, 20 Dec 2024 13:08:59 +0100
parents Meerwald/signature-utils.c@bd669312f068
children
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Meerwald-dir/signature-utils.c	Fri Dec 20 13:08:59 2024 +0100
@@ -0,0 +1,120 @@
+#include <string.h>
+#include <strings.h>
+#include "signature-utils.h"
+
+void init_signature_bits() {
+  bzero(signature, sizeof(signature));
+}
+
+void init_signature1_bits() {
+  bzero(signature1, sizeof(signature1));
+}
+
+void init_signature2_bits() {
+  bzero(signature2, sizeof(signature2));
+}
+
+int _get_signature_bit(char *s, int lim, int n) {
+  int byte = n >> 3;
+  int bit = n & 7;
+
+#ifdef DEBUG
+  if (byte < 0 || byte >= lim)
+    fprintf(stderr, "get_signature_bit?(): index out of range\n");
+#endif
+
+  return (s[byte] & (1 << bit)) >> bit;
+}
+
+int get_signature_bit(int n) {
+  return _get_signature_bit(signature, NSIGNATURE, n);
+}
+
+int get_signature1_bit(int n) {
+  return _get_signature_bit(signature1, NSIGNATURE, n);
+}
+
+int get_signature2_bit(int n) {
+  return _get_signature_bit(signature2, NSIGNATURE, n);
+}
+
+void _set_signature_bit(char *s, int limit, int n, int v) {
+  int byte = n >> 3;
+  int bit = n & 7;
+
+#ifdef DEBUG
+  if (byte < 0 || byte >= limit / 8)
+    fprintf(stderr, "get_signature_bit?(): index out of range\n");
+#endif
+
+  if (v)
+    s[byte] |= (1 << bit);
+  else
+    s[byte] &= ~(1 << bit);
+}
+
+void set_signature_bit(int n, int v) {
+  _set_signature_bit(signature, NSIGNATURE, n, v);
+}
+
+void set_signature1_bit(int n, int v) {
+  _set_signature_bit(signature1, NSIGNATURE, n, v);
+}
+
+void set_signature2_bit(int n, int v) {
+  _set_signature_bit(signature2, NSIGNATURE, n, v);
+}
+
+int _binstr_to_sig(const char *binstr, char *sig, int *bytes, int *bits) {
+  int n = strlen(binstr);
+  int i;
+
+  for (i = 0; i < n; i++) {
+    if (binstr[i] == '0')
+      _set_signature_bit(sig, NSIGNATURE, i, 0);
+    else if (binstr[i] == '1')
+      _set_signature_bit(sig, NSIGNATURE, i, 1);
+    else
+      return 0;
+  }
+
+  *bytes = (n % 8 > 0) ? n / 8 + 1 : n / 8;
+  *bits = n;
+
+  return 1;  
+}
+
+int binstr_to_sig(const char *binstr) {
+  return _binstr_to_sig(binstr, signature, &n_signature, &nbit_signature);
+}
+
+int binstr_to_sig1(const char *binstr) {
+  return _binstr_to_sig(binstr, signature1, &n_signature1, &nbit_signature1);
+}
+
+int binstr_to_sig2(const char *binstr) {
+  return _binstr_to_sig(binstr, signature2, &n_signature2, &nbit_signature2);
+}
+
+int _sig_to_binstr(char *binstr, char *sig, int bits) {
+  int i;
+
+  for (i = 0; i < bits; i++)
+    binstr[i] = _get_signature_bit(sig, NSIGNATURE, i) ? '1' : '0';
+
+  binstr[bits] = '\0';
+
+  return 1;
+}
+
+int sig_to_binstr(char *binstr) {
+  return _sig_to_binstr(binstr, signature, nbit_signature);
+}
+
+int sig1_to_binstr(char *binstr) {
+  return _sig_to_binstr(binstr, signature1, nbit_signature1);
+}
+
+int sig2_to_binstr(char *binstr) {
+  return _sig_to_binstr(binstr, signature2, nbit_signature2);
+}

Repositories maintained by Peter Meerwald, pmeerw@pmeerw.net.