+/*
+ * Copyright (c) 1987 Regents of the University of California.
+ * All rights reserved. The Berkeley software License Agreement
+ * specifies the terms and conditions for redistribution.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)chgbars.c 5.1 (Berkeley) %G%";
+#endif not lint
+
+/*
+ * Derived from original program by A. Dain Samples.
+ *
+ * The program chgbars will accept the output from a diff comparison of
+ * two versions of a file. It will then read the new version of the file
+ * and insert the appropriate troff commands to put change bars in the
+ * right margin. Typing 'chgbars' without any arguments will give you
+ * some documentation and an example.
+ *
+ * Caveat: If you make a change inside an equation or table, the
+ * preprocessors eqn and tbl may not like what chgbars does to the file.
+ * You may have to go into the output from chgbars to remove or rearrange
+ * some of the lines of the form '.mc | \"open' or '.mc \"close' in
+ * order to get through tbl or eqn.
+ *
+ * Unfortunately, users of RCS will be disappointed: one cannot use rcsdiff.
+ * Rcsdiff compares the files in the wrong order.
+ *
+ * There is a relatively easy way to do the job with the tools sed and awk.
+ * However, sed does not allow enough commands to process large documents.
+ * In the true spirit of a filter/tool, chgbars is limited only by the
+ * amount of memory on the machine, and is fast and useful.
+ *
+ * The modifications necessary are outlined:
+ *
+ * FORM OF DIFF OUTPUT COMMENT NEW SED COMMANDS
+ * ================================================================
+ * 100a means those lines 100a\\
+ * L1 were deleted from .mc |\\
+ * L2 oldfile .mc
+ * :
+ * Ln
+ * .
+ * ----------------------------------------------------------------
+ * 100c
+ * L1
+ * L2
+ * :
+ * Ln
+ * .
+ * means that line 100 in newfile replaced all those lines in oldfile.
+ * 100a
+ * .mc
+ * 99 a
+ * .mc |
+ * ----------------------------------------------------------------
+ * 100d that line was added 100a\\
+ * to oldfile .mc
+ * 99a\\
+ * .mc |
+ * ----------------------------------------------------------------
+ * 100,200d those lines were 200a\\
+ * added to oldfile .mc
+ * 99a\\
+ * .mc |
+ * ----------------------------------------------------------------
+ * 100,200c
+ * L1
+ * L2
+ * :
+ * Ln
+ * .
+ * means lines 100 to 200 of newfile replaced all the following lines
+ * in oldfile.
+ * 200a
+ * .mc
+ * 99a
+ * .mc |
+ * ----------------------------------------------------------------
+ */
+
+#include <stdio.h>
+#include <strings.h>
+#include <ctype.h>
+
+#define dbg(s) /* fprintf(stderr,"s\n") */
+#define none 0
+#define open 1
+#define close 2
+#define both 3
+
+char (*action)[];
+FILE *file1, *file2;
+char linebuf[1024];
+char nextch;
+int num1, num2, t, line;
+char lineact;
+
+#ifndef lint
+char copyright[] =
+"@(#) Copyright (c) 1986 Regents of the University of California.\n\
+ All rights reserved.\n";
+#endif not lint
+
+main(argc, argv)
+ int argc;
+ char *argv[];
+{
+ register char *p;
+ register int i;
+
+ if (argc < 2)
+ usage();
+ /* open $1 */
+ if (strcmp(argv[1], "-") == 0) {
+ file1 = stdin;
+ if (argc <= 2)
+ usage();
+ } else if ((file1 = fopen(argv[1], "r")) == NULL) {
+ fprintf(stderr, "error: can't open %s\n", argv[1]);
+ exit(1);
+ }
+ /*
+ * read each entry setting the appropriate entry in action[]
+ *
+ * get the first line number: since diff -e puts the numbers out
+ * in reverse order, this tells us how big to make the file
+ */
+ readline();
+ if (lineact == 'a')
+ t = num1;
+ else
+ t = num2;
+ action = (char (*)[]) malloc(t + 1);
+ for (p = (char *) action, i = 0; i < t; i++)
+ *p++ = (char) none;
+ while (!feof(file1)) {
+ if (lineact == 'a') {
+ (*action)[num1] = both;
+ skiptilldot();
+ } else {
+ (*action)[num1 - 1] = open;
+ (*action)[num2] = close;
+ if (lineact == 'c')
+ skiptilldot();
+ else
+ skiptilleol();
+ }
+ readline();
+ }
+ fclose(file1);
+ /* open $2 */
+ if (argc == 2)
+ file2 = stdin;
+ else
+ file2 = fopen(argv[2], "r");
+ if (file2 == NULL) {
+ fprintf(stderr, "can't open %2\n", argv[2]);
+ exit(1);
+ }
+ line = 0;
+ while (!feof(file2)) {
+ if (line != 0)
+ fputs(linebuf, stdout);
+ if (line <= t) {
+ switch ((*action)[line]) {
+ case open:
+ printf(".mc | \\\"open\n");
+ break;
+ case close:
+ printf(".mc \\\"close\n");
+ break;
+ case both:
+ printf(".mc | \\\"both\n");
+ printf(".mc\n");
+ break;
+ default:;
+ }
+ }
+ fgets(linebuf, sizeof(linebuf), file2);
+ line++;
+ }
+ if (line <= t) {
+ fprintf(stderr, "oops: number of lines read does not match\n");
+ fprintf(stderr, "number of lines expected\n");
+ exit(1);
+ }
+ exit(0);
+}
+
+usage()
+{
+
+ fprintf(stderr, "Usage:\n");
+ fprintf(stderr, "\tchgbars diff.out\n");
+ fprintf(stderr, "\t\t\treads the output from diff, and expects the\n");
+ fprintf(stderr, "\t\t\tfile to be modified on stdin\n");
+ fprintf(stderr, "\tchgbars diff.out file.tbm\n");
+ fprintf(stderr, "\t\t\tboth the output from diff and the file to be\n");
+ fprintf(stderr, "\t\t\tmodified are stated explicitly\n");
+ fprintf(stderr, "\tchgbars - file.tbm\n");
+ fprintf(stderr, "\t\t\treads the output from diff on stdin\n");
+ fprintf(stderr, "\nE.g.\n");
+ fprintf(stderr, "diff -b -e newfile oldfile | chgbars - newfile | vtroff -ms\n");
+ fprintf(stderr, "\t(note the order of the files in the diff command!)\n");
+ fprintf(stderr, "\n\nBe forewarned: chgbars does not know about tables or equations.\n");
+ fprintf(stderr, "If any part of a table or equation is changed, chgbars will insert the\n");
+ fprintf(stderr, ".mc commands, whether tbl or eqn likes it or not.\n");
+ fprintf(stderr, "This means that you may have to do some hand editing of the output of\n");
+ fprintf(stderr, "chgbars to make it acceptable to one or both of these preprocessors.\n");
+
+ exit(1);
+}
+
+readnum()
+{
+ int num;
+
+ dbg(readnum);
+ num = 0;
+ nextch = getc(file1);
+ while (isdigit(nextch)) {
+ num = num * 10 + nextch - '0';
+ nextch = getc(file1);
+ }
+ return num;
+}
+
+readline()
+{
+
+ dbg(readline);
+ num1 = readnum();
+ if (nextch == ',')
+ num2 = readnum();
+ else
+ num2 = num1;
+ lineact = nextch;
+}
+
+skiptilleol()
+{
+
+ dbg(skiptilleol);
+ while (nextch != '\n')
+ nextch = getc(file1);
+}
+
+skiptilldot()
+{
+
+ dbg(skiptilldot);
+ do {
+ if (fgets(linebuf, sizeof(linebuf), file1) == NULL) {
+ fprintf(stderr, "error reading file1\n");
+ exit(1);
+ }
+ } while (strcmp(linebuf, ".\n") != 0);
+}
projects / unix-history / commitdiff