Initial commit

fast_misc/str_change.c

@@ -0,0 +1,95 @@
+/*	Utility to change strings in binary files.
+	Reads from standard input, writes on standard output.
+	Only replaces one occurrence if the -s flag is given.
+*/
+
+#include <stdio.h>
+
+main(argc, argv)
+	char *argv[];
+{
+	register char *psrc;
+	register int ch;
+	int srclen;
+	int sflag = 0;
+	char *progname = argv[0];
+
+	while (argc > 1 && argv[1][0] == '-') {
+		switch(argv[1][1]) {
+		case 's':
+			sflag = 1;
+			break;
+		default:
+			fprintf(stderr,
+			"Usage: %s [-s] <originalstring> <replacementstring>\n",
+			progname);
+			exit(1);
+		}
+		argc--;
+		argv++;
+	}
+	if (argc != 3) {
+		fprintf(stderr,
+			"Usage: %s [-s] <originalstring> <replacementstring>\n",
+			progname);
+		exit(1);
+	}
+
+	psrc = argv[1];
+	srclen = strlen(psrc);
+	if (srclen == 0) {
+		fprintf(stderr,
+			"%s: originalstring must have length > 0\n",
+			progname);
+		exit(1);
+	}
+	for (;;) {
+		ch = getchar();
+		if (ch == EOF) exit(0);
+		if (ch != (*psrc & 0377)) {
+			putchar(ch);
+			continue;
+		}
+		do {
+			psrc++;
+			ch = getchar();
+		} while (ch && ch == (*psrc & 0377));
+		if (ch != EOF) ungetc(ch, stdin);
+		if (*psrc == '\0') {
+			/* we have a match */
+			register int i;
+			register char *prepl = argv[2];
+
+			for (i = srclen; i; i--) {
+				if (*prepl) {
+					putchar(*prepl);
+					prepl++;
+				}
+				else putchar('\0');
+			}
+			while (*prepl) {
+				putchar(*prepl);
+				prepl++;
+				if (ch != EOF) ch = getchar();
+			}
+			if (sflag) {
+				break;
+			}
+		}
+		else {
+			register char *p = argv[1];
+			
+			while (p < psrc) {
+				putchar(*p);
+				p++;
+			}
+			if (ch == EOF) exit(0);
+		}
+		psrc = argv[1];
+	}
+	if (ch == EOF) exit(0);
+	while ((ch = getchar()) != EOF) {
+		putchar(ch);
+	}
+	exit(0);
+}