+/* Three way file comparison program (diff3) for Project GNU.
+ Copyright (C) 1988, 1989, 1992 Free Software Foundation, Inc.
+
+ 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; either version 2, or (at your option)
+ any later version.
+
+ 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
+\f
+/* Written by Randy Smith */
+
+#if __STDC__
+#define VOID void
+#else
+#define VOID char
+#endif
+
+#include <stdio.h>
+#include <ctype.h>
+#include "getopt.h"
+#include "system.h"
+
+/*
+ * Internal data structures and macros for the diff3 program; includes
+ * data structures for both diff3 diffs and normal diffs.
+ */
+
+/* Different files within a three way diff. */
+#define FILE0 0
+#define FILE1 1
+#define FILE2 2
+
+/*
+ * A three way diff is built from two two-way diffs; the file which
+ * the two two-way diffs share is:
+ */
+#define FILEC FILE2
+
+/*
+ * Different files within a two way diff.
+ * FC is the common file, FO the other file.
+ */
+#define FO 0
+#define FC 1
+
+/* The ranges are indexed by */
+#define START 0
+#define END 1
+
+enum diff_type {
+ ERROR, /* Should not be used */
+ ADD, /* Two way diff add */
+ CHANGE, /* Two way diff change */
+ DELETE, /* Two way diff delete */
+ DIFF_ALL, /* All three are different */
+ DIFF_1ST, /* Only the first is different */
+ DIFF_2ND, /* Only the second */
+ DIFF_3RD /* Only the third */
+};
+
+/* Two way diff */
+struct diff_block {
+ int ranges[2][2]; /* Ranges are inclusive */
+ char **lines[2]; /* The actual lines (may contain nulls) */
+ int *lengths[2]; /* Line lengths (including newlines, if any) */
+ struct diff_block *next;
+};
+
+/* Three way diff */
+
+struct diff3_block {
+ enum diff_type correspond; /* Type of diff */
+ int ranges[3][2]; /* Ranges are inclusive */
+ char **lines[3]; /* The actual lines (may contain nulls) */
+ int *lengths[3]; /* Line lengths (including newlines, if any) */
+ struct diff3_block *next;
+};
+
+/*
+ * Access the ranges on a diff block.
+ */
+#define D_LOWLINE(diff, filenum) \
+ ((diff)->ranges[filenum][START])
+#define D_HIGHLINE(diff, filenum) \
+ ((diff)->ranges[filenum][END])
+#define D_NUMLINES(diff, filenum) \
+ (D_HIGHLINE (diff, filenum) - D_LOWLINE (diff, filenum) + 1)
+
+/*
+ * Access the line numbers in a file in a diff by relative line
+ * numbers (i.e. line number within the diff itself). Note that these
+ * are lvalues and can be used for assignment.
+ */
+#define D_RELNUM(diff, filenum, linenum) \
+ ((diff)->lines[filenum][linenum])
+#define D_RELLEN(diff, filenum, linenum) \
+ ((diff)->lengths[filenum][linenum])
+
+/*
+ * And get at them directly, when that should be necessary.
+ */
+#define D_LINEARRAY(diff, filenum) \
+ ((diff)->lines[filenum])
+#define D_LENARRAY(diff, filenum) \
+ ((diff)->lengths[filenum])
+
+/*
+ * Next block.
+ */
+#define D_NEXT(diff) ((diff)->next)
+
+/*
+ * Access the type of a diff3 block.
+ */
+#define D3_TYPE(diff) ((diff)->correspond)
+
+/*
+ * Line mappings based on diffs. The first maps off the top of the
+ * diff, the second off of the bottom.
+ */
+#define D_HIGH_MAPLINE(diff, fromfile, tofile, lineno) \
+ ((lineno) \
+ - D_HIGHLINE ((diff), (fromfile)) \
+ + D_HIGHLINE ((diff), (tofile)))
+
+#define D_LOW_MAPLINE(diff, fromfile, tofile, lineno) \
+ ((lineno) \
+ - D_LOWLINE ((diff), (fromfile)) \
+ + D_LOWLINE ((diff), (tofile)))
+
+/*
+ * General memory allocation function.
+ */
+#define ALLOCATE(number, type) \
+ (type *) xmalloc ((number) * sizeof (type))
+\f
+/* Options variables for flags set on command line. */
+
+/* If nonzero, treat all files as text files, never as binary. */
+static int always_text;
+
+/* If nonzero, write out an ed script instead of the standard diff3 format. */
+static int edscript;
+
+/* If nonzero, in the case of overlapping diffs (type DIFF_ALL),
+ preserve the lines which would normally be deleted from
+ file 1 with a special flagging mechanism. */
+static int flagging;
+
+/* Number of lines to keep in identical prefix and suffix. */
+static int horizon_lines = 10;
+
+/* If nonzero, do not output information for overlapping diffs. */
+static int simple_only;
+
+/* If nonzero, do not output information for non-overlapping diffs. */
+static int overlap_only;
+
+/* If nonzero, show information for DIFF_2ND diffs. */
+static int show_2nd;
+
+/* If nonzero, include `:wq' at the end of the script
+ to write out the file being edited. */
+static int finalwrite;
+
+/* If nonzero, output a merged file. */
+static int merge;
+
+static char *argv0;
+
+/*
+ * Forward function declarations.
+ */
+static int myread ();
+static void fatal ();
+static void perror_with_exit ();
+static struct diff_block *process_diff ();
+static struct diff3_block *make_3way_diff ();
+static void output_diff3 ();
+static int output_diff3_edscript ();
+static int output_diff3_merge ();
+static void usage ();
+
+static struct diff3_block *using_to_diff3_block ();
+static int copy_stringlist ();
+static struct diff3_block *create_diff3_block ();
+static int compare_line_list ();
+
+static char *read_diff ();
+static enum diff_type process_diff_control ();
+static char *scan_diff_line ();
+
+static struct diff3_block *reverse_diff3_blocklist ();
+
+VOID *xmalloc ();
+static VOID *xrealloc ();
+
+static char diff_program[] = DIFF_PROGRAM;
+
+static struct option longopts[] =
+{
+ {"text", 0, NULL, 'a'},
+ {"show-all", 0, NULL, 'A'},
+ {"ed", 0, NULL, 'e'},
+ {"show-overlap", 0, NULL, 'E'},
+ {"label", 1, NULL, 'L'},
+ {"merge", 0, NULL, 'm'},
+ {"overlap-only", 0, NULL, 'x'},
+ {"easy-only", 0, NULL, '3'},
+ {"version", 0, NULL, 'v'},
+ {0, 0, 0, 0}
+};
+
+/*
+ * Main program. Calls diff twice on two pairs of input files,
+ * combines the two diffs, and outputs them.
+ */
+int
+main (argc, argv)
+ int argc;
+ char **argv;
+{
+ extern char *version_string;
+ int c, i;
+ int mapping[3];
+ int rev_mapping[3];
+ int incompat;
+ int conflicts_found;
+ struct diff_block *thread0, *thread1, *last_block;
+ struct diff3_block *diff3;
+ int tag_count = 0;
+ char *tag_strings[3];
+ extern char *optarg;
+ char *commonname;
+ char **file;
+ struct stat statb;
+
+ incompat = 0;
+
+ argv0 = argv[0];
+
+ while ((c = getopt_long (argc, argv, "aeimvx3AEXL:", longopts, (int *) 0))
+ != EOF)
+ {
+ switch (c)
+ {
+ case 'a':
+ always_text = 1;
+ break;
+ case 'A':
+ show_2nd = 1;
+ flagging = 1;
+ incompat++;
+ break;
+ case 'x':
+ overlap_only = 1;
+ incompat++;
+ break;
+ case '3':
+ simple_only = 1;
+ incompat++;
+ break;
+ case 'i':
+ finalwrite = 1;
+ break;
+ case 'm':
+ merge = 1;
+ break;
+ case 'X':
+ overlap_only = 1;
+ /* Falls through */
+ case 'E':
+ flagging = 1;
+ /* Falls through */
+ case 'e':
+ incompat++;
+ break;
+ case 'v':
+ fprintf (stderr, "GNU diff3 version %s\n", version_string);
+ break;
+ case 'L':
+ /* Handle up to three -L options. */
+ if (tag_count < 3)
+ {
+ tag_strings[tag_count++] = optarg;
+ break;
+ }
+ /* Falls through */
+ default:
+ usage ();
+ /* NOTREACHED */
+ }
+ }
+
+ edscript = incompat & ~merge; /* -AeExX3 without -m implies ed script. */
+ show_2nd |= ~incompat & merge; /* -m without -AeExX3 implies -A. */
+ flagging |= ~incompat & merge;
+
+ if (incompat > 1 /* Ensure at most one of -AeExX3. */
+ || finalwrite & merge /* -i -m would rewrite input file. */
+ || (tag_count && ! flagging) /* -L requires one of -AEX. */
+ || argc - optind != 3)
+ usage ();
+
+ file = &argv[optind];
+
+ for (i = tag_count; i < 3; i++)
+ tag_strings[i] = file[i];
+
+ /* Always compare file1 to file2, even if file2 is "-".
+ This is needed for -mAeExX3. Using the file0 as
+ the common file would produce wrong results, because if the
+ file0-file1 diffs didn't line up with the file0-file2 diffs
+ (which is entirely possible since we don't use diff's -n option),
+ diff3 might report phantom changes from file1 to file2. */
+
+ if (strcmp (file[2], "-") == 0)
+ {
+ /* Sigh. We've got standard input as the last arg. We can't
+ call diff twice on stdin. Use the middle arg as the common
+ file instead. */
+ if (strcmp (file[0], "-") == 0 || strcmp (file[1], "-") == 0)
+ fatal ("`-' specified for more than one input file");
+ mapping[0] = 0;
+ mapping[1] = 2;
+ mapping[2] = 1;
+ }
+ else
+ {
+ /* Normal, what you'd expect */
+ mapping[0] = 0;
+ mapping[1] = 1;
+ mapping[2] = 2;
+ }
+
+ for (i = 0; i < 3; i++)
+ rev_mapping[mapping[i]] = i;
+
+ for (i = 0; i < 3; i++)
+ if (strcmp (file[i], "-") != 0)
+ if (stat (file[i], &statb) < 0)
+ perror_with_exit (file[i]);
+ else if (S_ISDIR(statb.st_mode))
+ {
+ fprintf (stderr, "%s: %s: Is a directory\n", argv0, file[i]);
+ exit (2);
+ }
+
+
+ commonname = file[rev_mapping[FILEC]];
+ thread1 = process_diff (file[rev_mapping[FILE1]], commonname, &last_block);
+ if (thread1)
+ for (i = 0; i < 2; i++)
+ {
+ horizon_lines = max (horizon_lines, D_NUMLINES (thread1, i));
+ horizon_lines = max (horizon_lines, D_NUMLINES (last_block, i));
+ }
+ thread0 = process_diff (file[rev_mapping[FILE0]], commonname, &last_block);
+ diff3 = make_3way_diff (thread0, thread1);
+ if (edscript)
+ conflicts_found
+ = output_diff3_edscript (stdout, diff3, mapping, rev_mapping,
+ tag_strings[0], tag_strings[1], tag_strings[2]);
+ else if (merge)
+ {
+ if (! freopen (file[rev_mapping[FILE0]], "r", stdin))
+ perror_with_exit (file[rev_mapping[FILE0]]);
+ conflicts_found
+ = output_diff3_merge (stdin, stdout, diff3, mapping, rev_mapping,
+ tag_strings[0], tag_strings[1], tag_strings[2]);
+ if (ferror (stdin))
+ fatal ("read error");
+ }
+ else
+ {
+ output_diff3 (stdout, diff3, mapping, rev_mapping);
+ conflicts_found = 0;
+ }
+
+ if (ferror (stdout) || fclose (stdout) != 0)
+ fatal ("write error");
+ exit (conflicts_found);
+ return conflicts_found;
+}
+
+/*
+ * Explain, patiently and kindly, how to use this program. Then exit.
+ */
+static void
+usage ()
+{
+ fprintf (stderr, "\
+Usage: %s [options] my-file older-file your-file\n\
+Options:\n\
+ [-exAEX3v] [-i|-m] [-L label1 [-L label2 [-L label3]]] [--text] [--ed]\n\
+ [--merge] [--show-all] [--show-overlap] [--overlap-only] [--easy-only]\n\
+ [--label=label1 [--label=label2 [--label=label3]]] [--version]\n\
+ Only one of [exAEX3] is allowed\n", argv0);
+ exit (2);
+}
+\f
+/*
+ * Routines that combine the two diffs together into one. The
+ * algorithm used follows:
+ *
+ * File2 is shared in common between the two diffs.
+ * Diff02 is the diff between 0 and 2.
+ * Diff12 is the diff between 1 and 2.
+ *
+ * 1) Find the range for the first block in File2.
+ * a) Take the lowest of the two ranges (in File2) in the two
+ * current blocks (one from each diff) as being the low
+ * water mark. Assign the upper end of this block as
+ * being the high water mark and move the current block up
+ * one. Mark the block just moved over as to be used.
+ * b) Check the next block in the diff that the high water
+ * mark is *not* from.
+ *
+ * *If* the high water mark is above
+ * the low end of the range in that block,
+ *
+ * mark that block as to be used and move the current
+ * block up. Set the high water mark to the max of
+ * the high end of this block and the current. Repeat b.
+ *
+ * 2) Find the corresponding ranges in File0 (from the blocks
+ * in diff02; line per line outside of diffs) and in File1.
+ * Create a diff3_block, reserving space as indicated by the ranges.
+ *
+ * 3) Copy all of the pointers for file2 in. At least for now,
+ * do bcmp's between corresponding strings in the two diffs.
+ *
+ * 4) Copy all of the pointers for file0 and 1 in. Get what you
+ * need from file2 (when there isn't a diff block, it's
+ * identical to file2 within the range between diff blocks).
+ *
+ * 5) If the diff blocks you used came from only one of the two
+ * strings of diffs, then that file (i.e. the one other than
+ * the common file in that diff) is the odd person out. If you used
+ * diff blocks from both sets, check to see if files 0 and 1 match:
+ *
+ * Same number of lines? If so, do a set of bcmp's (if a
+ * bcmp matches; copy the pointer over; it'll be easier later
+ * if you have to do any compares). If they match, 0 & 1 are
+ * the same. If not, all three different.
+ *
+ * Then you do it again, until you run out of blocks.
+ *
+ */
+
+/*
+ * This routine makes a three way diff (chain of diff3_block's) from two
+ * two way diffs (chains of diff_block's). It is assumed that each of
+ * the two diffs passed are onto the same file (i.e. that each of the
+ * diffs were made "to" the same file). The three way diff pointer
+ * returned will have numbering FILE0--the other file in diff02,
+ * FILE1--the other file in diff12, and FILEC--the common file.
+ */
+static struct diff3_block *
+make_3way_diff (thread0, thread1)
+ struct diff_block *thread0, *thread1;
+{
+/*
+ * This routine works on the two diffs passed to it as threads.
+ * Thread number 0 is diff02, thread number 1 is diff12. The USING
+ * array is set to the base of the list of blocks to be used to
+ * construct each block of the three way diff; if no blocks from a
+ * particular thread are to be used, that element of the using array
+ * is set to 0. The elements LAST_USING array are set to the last
+ * elements on each of the using lists.
+ *
+ * The HIGH_WATER_MARK is set to the highest line number in the common file
+ * described in any of the diffs in either of the USING lists. The
+ * HIGH_WATER_THREAD names the thread. Similarly the BASE_WATER_MARK
+ * and BASE_WATER_THREAD describe the lowest line number in the common file
+ * described in any of the diffs in either of the USING lists. The
+ * HIGH_WATER_DIFF is the diff from which the HIGH_WATER_MARK was
+ * taken.
+ *
+ * The HIGH_WATER_DIFF should always be equal to LAST_USING
+ * [HIGH_WATER_THREAD]. The OTHER_DIFF is the next diff to check for
+ * higher water, and should always be equal to
+ * CURRENT[HIGH_WATER_THREAD ^ 0x1]. The OTHER_THREAD is the thread
+ * in which the OTHER_DIFF is, and hence should always be equal to
+ * HIGH_WATER_THREAD ^ 0x1.
+ *
+ * The variable LAST_DIFF is kept set to the last diff block produced
+ * by this routine, for line correspondence purposes between that diff
+ * and the one currently being worked on. It is initialized to
+ * ZERO_DIFF before any blocks have been created.
+ */
+
+ struct diff_block
+ *using[2],
+ *last_using[2],
+ *current[2];
+
+ int
+ high_water_mark;
+
+ int
+ high_water_thread,
+ base_water_thread,
+ other_thread;
+
+ struct diff_block
+ *high_water_diff,
+ *other_diff;
+
+ struct diff3_block
+ *result,
+ *tmpblock,
+ **result_end,
+ *last_diff3;
+
+ static struct diff3_block zero_diff3 = {
+ ERROR,
+ { {0, 0}, {0, 0}, {0, 0} },
+ { (char **) 0, (char **) 0, (char **) 0 },
+ { (int *) 0, (int *) 0, (int *) 0 },
+ (struct diff3_block *) 0
+ };
+
+ /* Initialization */
+ result = 0;
+ result_end = &result;
+ current[0] = thread0; current[1] = thread1;
+ last_diff3 = &zero_diff3;
+
+ /* Sniff up the threads until we reach the end */
+
+ while (current[0] || current[1])
+ {
+ using[0] = using[1] = last_using[0] = last_using[1] =
+ (struct diff_block *) 0;
+
+ /* Setup low and high water threads, diffs, and marks. */
+ if (!current[0])
+ base_water_thread = 1;
+ else if (!current[1])
+ base_water_thread = 0;
+ else
+ base_water_thread =
+ (D_LOWLINE (current[0], FC) > D_LOWLINE (current[1], FC));
+
+ high_water_thread = base_water_thread;
+
+ high_water_diff = current[high_water_thread];
+
+#if 0
+ /* low and high waters start off same diff */
+ base_water_mark = D_LOWLINE (high_water_diff, FC);
+#endif
+
+ high_water_mark = D_HIGHLINE (high_water_diff, FC);
+
+ /* Make the diff you just got info from into the using class */
+ using[high_water_thread]
+ = last_using[high_water_thread]
+ = high_water_diff;
+ current[high_water_thread] = high_water_diff->next;
+ last_using[high_water_thread]->next
+ = (struct diff_block *) 0;
+
+ /* And mark the other diff */
+ other_thread = high_water_thread ^ 0x1;
+ other_diff = current[other_thread];
+
+ /* Shuffle up the ladder, checking the other diff to see if it
+ needs to be incorporated. */
+ while (other_diff
+ && D_LOWLINE (other_diff, FC) <= high_water_mark + 1)
+ {
+
+ /* Incorporate this diff into the using list. Note that
+ this doesn't take it off the current list */
+ if (using[other_thread])
+ last_using[other_thread]->next = other_diff;
+ else
+ using[other_thread] = other_diff;
+ last_using[other_thread] = other_diff;
+
+ /* Take it off the current list. Note that this following
+ code assumes that other_diff enters it equal to
+ current[high_water_thread ^ 0x1] */
+ current[other_thread]
+ = current[other_thread]->next;
+ other_diff->next
+ = (struct diff_block *) 0;
+
+ /* Set the high_water stuff
+ If this comparison is equal, then this is the last pass
+ through this loop; since diff blocks within a given
+ thread cannot overlap, the high_water_mark will be
+ *below* the range_start of either of the next diffs. */
+
+ if (high_water_mark < D_HIGHLINE (other_diff, FC))
+ {
+ high_water_thread ^= 1;
+ high_water_diff = other_diff;
+ high_water_mark = D_HIGHLINE (other_diff, FC);
+ }
+
+ /* Set the other diff */
+ other_thread = high_water_thread ^ 0x1;
+ other_diff = current[other_thread];
+ }
+
+ /* The using lists contain a list of all of the blocks to be
+ included in this diff3_block. Create it. */
+
+ tmpblock = using_to_diff3_block (using, last_using,
+ base_water_thread, high_water_thread,
+ last_diff3);
+
+ if (!tmpblock)
+ fatal ("internal error: screwup in format of diff blocks");
+
+ /* Put it on the list. */
+ *result_end = tmpblock;
+ result_end = &tmpblock->next;
+
+ /* Set up corresponding lines correctly. */
+ last_diff3 = tmpblock;
+ }
+ return result;
+}
+
+/*
+ * using_to_diff3_block:
+ * This routine takes two lists of blocks (from two separate diff
+ * threads) and puts them together into one diff3 block.
+ * It then returns a pointer to this diff3 block or 0 for failure.
+ *
+ * All arguments besides using are for the convenience of the routine;
+ * they could be derived from the using array.
+ * LAST_USING is a pair of pointers to the last blocks in the using
+ * structure.
+ * LOW_THREAD and HIGH_THREAD tell which threads contain the lowest
+ * and highest line numbers for File0.
+ * last_diff3 contains the last diff produced in the calling routine.
+ * This is used for lines mappings which would still be identical to
+ * the state that diff ended in.
+ *
+ * A distinction should be made in this routine between the two diffs
+ * that are part of a normal two diff block, and the three diffs that
+ * are part of a diff3_block.
+ */
+static struct diff3_block *
+using_to_diff3_block (using, last_using, low_thread, high_thread, last_diff3)
+ struct diff_block
+ *using[2],
+ *last_using[2];
+ int low_thread, high_thread;
+ struct diff3_block *last_diff3;
+{
+ int low[2], high[2];
+ struct diff3_block *result;
+ struct diff_block *ptr;
+ int d, i;
+
+ /* Find the range in the common file. */
+ int lowc = D_LOWLINE (using[low_thread], FC);
+ int highc = D_HIGHLINE (last_using[high_thread], FC);
+
+ /* Find the ranges in the other files.
+ If using[d] is null, that means that the file to which that diff
+ refers is equivalent to the common file over this range. */
+
+ for (d = 0; d < 2; d++)
+ if (using[d])
+ {
+ low[d] = D_LOW_MAPLINE (using[d], FC, FO, lowc);
+ high[d] = D_HIGH_MAPLINE (last_using[d], FC, FO, highc);
+ }
+ else
+ {
+ low[d] = D_HIGH_MAPLINE (last_diff3, FILEC, FILE0 + d, lowc);
+ high[d] = D_HIGH_MAPLINE (last_diff3, FILEC, FILE0 + d, highc);
+ }
+
+ /* Create a block with the appropriate sizes */
+ result = create_diff3_block (low[0], high[0], low[1], high[1], lowc, highc);
+
+ /* Copy information for the common file.
+ Return with a zero if any of the compares failed. */
+
+ for (d = 0; d < 2; d++)
+ for (ptr = using[d]; ptr; ptr = D_NEXT (ptr))
+ {
+ int result_offset = D_LOWLINE (ptr, FC) - lowc;
+
+ if (!copy_stringlist (D_LINEARRAY (ptr, FC),
+ D_LENARRAY (ptr, FC),
+ D_LINEARRAY (result, FILEC) + result_offset,
+ D_LENARRAY (result, FILEC) + result_offset,
+ D_NUMLINES (ptr, FC)))
+ return 0;
+ }
+
+ /* Copy information for file d. First deal with anything that might be
+ before the first diff. */
+
+ for (d = 0; d < 2; d++)
+ {
+ struct diff_block *u = using[d];
+ int lo = low[d], hi = high[d];
+
+ for (i = 0;
+ i + lo < (u ? D_LOWLINE (u, FO) : hi + 1);
+ i++)
+ {
+ D_RELNUM (result, FILE0 + d, i) = D_RELNUM (result, FILEC, i);
+ D_RELLEN (result, FILE0 + d, i) = D_RELLEN (result, FILEC, i);
+ }
+
+ for (ptr = u; ptr; ptr = D_NEXT (ptr))
+ {
+ int result_offset = D_LOWLINE (ptr, FO) - lo;
+ int linec;
+
+ if (!copy_stringlist (D_LINEARRAY (ptr, FO),
+ D_LENARRAY (ptr, FO),
+ D_LINEARRAY (result, FILE0 + d) + result_offset,
+ D_LENARRAY (result, FILE0 + d) + result_offset,
+ D_NUMLINES (ptr, FO)))
+ return 0;
+
+ /* Catch the lines between here and the next diff */
+ linec = D_HIGHLINE (ptr, FC) + 1 - lowc;
+ for (i = D_HIGHLINE (ptr, FO) + 1 - lo;
+ i < (D_NEXT (ptr) ? D_LOWLINE (D_NEXT (ptr), FO) : hi + 1) - lo;
+ i++)
+ {
+ D_RELNUM (result, FILE0 + d, i) = D_RELNUM (result, FILEC, linec);
+ D_RELLEN (result, FILE0 + d, i) = D_RELLEN (result, FILEC, linec);
+ linec++;
+ }
+ }
+ }
+
+ /* Set correspond */
+ if (!using[0])
+ D3_TYPE (result) = DIFF_2ND;
+ else if (!using[1])
+ D3_TYPE (result) = DIFF_1ST;
+ else
+ {
+ int nl0 = D_NUMLINES (result, FILE0);
+ int nl1 = D_NUMLINES (result, FILE1);
+
+ if (nl0 != nl1
+ || !compare_line_list (D_LINEARRAY (result, FILE0),
+ D_LENARRAY (result, FILE0),
+ D_LINEARRAY (result, FILE1),
+ D_LENARRAY (result, FILE1),
+ nl0))
+ D3_TYPE (result) = DIFF_ALL;
+ else
+ D3_TYPE (result) = DIFF_3RD;
+ }
+
+ return result;
+}
+
+/*
+ * This routine copies pointers from a list of strings to a different list
+ * of strings. If a spot in the second list is already filled, it
+ * makes sure that it is filled with the same string; if not it
+ * returns 0, the copy incomplete.
+ * Upon successful completion of the copy, it returns 1.
+ */
+static int
+copy_stringlist (fromptrs, fromlengths, toptrs, tolengths, copynum)
+ char *fromptrs[], *toptrs[];
+ int *fromlengths, *tolengths;
+ int copynum;
+{
+ register char
+ **f = fromptrs,
+ **t = toptrs;
+ register int
+ *fl = fromlengths,
+ *tl = tolengths;
+
+ while (copynum--)
+ {
+ if (*t)
+ { if (*fl != *tl || bcmp (*f, *t, *fl)) return 0; }
+ else
+ { *t = *f ; *tl = *fl; }
+
+ t++; f++; tl++; fl++;
+ }
+ return 1;
+}
+
+/*
+ * Create a diff3_block, with ranges as specified in the arguments.
+ * Allocate the arrays for the various pointers (and zero them) based
+ * on the arguments passed. Return the block as a result.
+ */
+static struct diff3_block *
+create_diff3_block (low0, high0, low1, high1, low2, high2)
+ register int low0, high0, low1, high1, low2, high2;
+{
+ struct diff3_block *result = ALLOCATE (1, struct diff3_block);
+ int numlines;
+
+ D3_TYPE (result) = ERROR;
+ D_NEXT (result) = 0;
+
+ /* Assign ranges */
+ D_LOWLINE (result, FILE0) = low0;
+ D_HIGHLINE (result, FILE0) = high0;
+ D_LOWLINE (result, FILE1) = low1;
+ D_HIGHLINE (result, FILE1) = high1;
+ D_LOWLINE (result, FILE2) = low2;
+ D_HIGHLINE (result, FILE2) = high2;
+
+ /* Allocate and zero space */
+ numlines = D_NUMLINES (result, FILE0);
+ if (numlines)
+ {
+ D_LINEARRAY (result, FILE0) = ALLOCATE (numlines, char *);
+ D_LENARRAY (result, FILE0) = ALLOCATE (numlines, int);
+ bzero (D_LINEARRAY (result, FILE0), (numlines * sizeof (char *)));
+ bzero (D_LENARRAY (result, FILE0), (numlines * sizeof (int)));
+ }
+ else
+ {
+ D_LINEARRAY (result, FILE0) = (char **) 0;
+ D_LENARRAY (result, FILE0) = (int *) 0;
+ }
+
+ numlines = D_NUMLINES (result, FILE1);
+ if (numlines)
+ {
+ D_LINEARRAY (result, FILE1) = ALLOCATE (numlines, char *);
+ D_LENARRAY (result, FILE1) = ALLOCATE (numlines, int);
+ bzero (D_LINEARRAY (result, FILE1), (numlines * sizeof (char *)));
+ bzero (D_LENARRAY (result, FILE1), (numlines * sizeof (int)));
+ }
+ else
+ {
+ D_LINEARRAY (result, FILE1) = (char **) 0;
+ D_LENARRAY (result, FILE1) = (int *) 0;
+ }
+
+ numlines = D_NUMLINES (result, FILE2);
+ if (numlines)
+ {
+ D_LINEARRAY (result, FILE2) = ALLOCATE (numlines, char *);
+ D_LENARRAY (result, FILE2) = ALLOCATE (numlines, int);
+ bzero (D_LINEARRAY (result, FILE2), (numlines * sizeof (char *)));
+ bzero (D_LENARRAY (result, FILE2), (numlines * sizeof (int)));
+ }
+ else
+ {
+ D_LINEARRAY (result, FILE2) = (char **) 0;
+ D_LENARRAY (result, FILE2) = (int *) 0;
+ }
+
+ /* Return */
+ return result;
+}
+
+/*
+ * Compare two lists of lines of text.
+ * Return 1 if they are equivalent, 0 if not.
+ */
+static int
+compare_line_list (list1, lengths1, list2, lengths2, nl)
+ char *list1[], *list2[];
+ int *lengths1, *lengths2;
+ int nl;
+{
+ char
+ **l1 = list1,
+ **l2 = list2;
+ int
+ *lgths1 = lengths1,
+ *lgths2 = lengths2;
+
+ while (nl--)
+ if (!*l1 || !*l2 || *lgths1 != *lgths2++
+ || bcmp (*l1++, *l2++, *lgths1++))
+ return 0;
+ return 1;
+}
+\f
+/*
+ * Routines to input and parse two way diffs.
+ */
+
+extern char **environ;
+
+#define DIFF_CHUNK_SIZE 10000
+
+static struct diff_block *
+process_diff (filea, fileb, last_block)
+ char *filea, *fileb;
+ struct diff_block **last_block;
+{
+ char *diff_contents;
+ char *diff_limit;
+ char *scan_diff;
+ enum diff_type dt;
+ int i;
+ struct diff_block *block_list, **block_list_end, *bptr;
+
+ diff_limit = read_diff (filea, fileb, &diff_contents);
+ scan_diff = diff_contents;
+ block_list_end = &block_list;
+
+ while (scan_diff < diff_limit)
+ {
+ bptr = ALLOCATE (1, struct diff_block);
+ bptr->lines[0] = bptr->lines[1] = (char **) 0;
+ bptr->lengths[0] = bptr->lengths[1] = (int *) 0;
+
+ dt = process_diff_control (&scan_diff, bptr);
+ if (dt == ERROR || *scan_diff != '\n')
+ {
+ fprintf (stderr, "%s: diff error: ", argv0);
+ do
+ {
+ putc (*scan_diff, stderr);
+ }
+ while (*scan_diff++ != '\n');
+ exit (2);
+ }
+ scan_diff++;
+
+ /* Force appropriate ranges to be null, if necessary */
+ switch (dt)
+ {
+ case ADD:
+ bptr->ranges[0][0]++;
+ break;
+ case DELETE:
+ bptr->ranges[1][0]++;
+ break;
+ case CHANGE:
+ break;
+ default:
+ fatal ("internal error: invalid diff type in process_diff");
+ break;
+ }
+
+ /* Allocate space for the pointers for the lines from filea, and
+ parcel them out among these pointers */
+ if (dt != ADD)
+ {
+ int numlines = D_NUMLINES (bptr, 0);
+ bptr->lines[0] = ALLOCATE (numlines, char *);
+ bptr->lengths[0] = ALLOCATE (numlines, int);
+ for (i = 0; i < numlines; i++)
+ scan_diff = scan_diff_line (scan_diff,
+ &(bptr->lines[0][i]),
+ &(bptr->lengths[0][i]),
+ diff_limit,
+ '<');
+ }
+
+ /* Get past the separator for changes */
+ if (dt == CHANGE)
+ {
+ if (strncmp (scan_diff, "---\n", 4))
+ fatal ("invalid diff format; invalid change separator");
+ scan_diff += 4;
+ }
+
+ /* Allocate space for the pointers for the lines from fileb, and
+ parcel them out among these pointers */
+ if (dt != DELETE)
+ {
+ int numlines = D_NUMLINES (bptr, 1);
+ bptr->lines[1] = ALLOCATE (numlines, char *);
+ bptr->lengths[1] = ALLOCATE (numlines, int);
+ for (i = 0; i < numlines; i++)
+ scan_diff = scan_diff_line (scan_diff,
+ &(bptr->lines[1][i]),
+ &(bptr->lengths[1][i]),
+ diff_limit,
+ '>');
+ }
+
+ /* Place this block on the blocklist. */
+ *block_list_end = bptr;
+ block_list_end = &bptr->next;
+ }
+
+ *block_list_end = 0;
+ *last_block = bptr;
+ return block_list;
+}
+
+/*
+ * This routine will parse a normal format diff control string. It
+ * returns the type of the diff (ERROR if the format is bad). All of
+ * the other important information is filled into to the structure
+ * pointed to by db, and the string pointer (whose location is passed
+ * to this routine) is updated to point beyond the end of the string
+ * parsed. Note that only the ranges in the diff_block will be set by
+ * this routine.
+ *
+ * If some specific pair of numbers has been reduced to a single
+ * number, then both corresponding numbers in the diff block are set
+ * to that number. In general these numbers are interpetted as ranges
+ * inclusive, unless being used by the ADD or DELETE commands. It is
+ * assumed that these will be special cased in a superior routine.
+ */
+
+static enum diff_type
+process_diff_control (string, db)
+ char **string;
+ struct diff_block *db;
+{
+ char *s = *string;
+ int holdnum;
+ enum diff_type type;
+
+/* These macros are defined here because they can use variables
+ defined in this function. Don't try this at home kids, we're
+ trained professionals!
+
+ Also note that SKIPWHITE only recognizes tabs and spaces, and
+ that READNUM can only read positive, integral numbers */
+
+#define SKIPWHITE(s) { while (*s == ' ' || *s == '\t') s++; }
+#define READNUM(s, num) \
+ { if (!isdigit (*s)) return ERROR; holdnum = 0; \
+ do { holdnum = (*s++ - '0' + holdnum * 10); } \
+ while (isdigit (*s)); (num) = holdnum; }
+
+ /* Read first set of digits */
+ SKIPWHITE (s);
+ READNUM (s, db->ranges[0][START]);
+
+ /* Was that the only digit? */
+ SKIPWHITE (s);
+ if (*s == ',')
+ {
+ /* Get the next digit */
+ s++;
+ READNUM (s, db->ranges[0][END]);
+ }
+ else
+ db->ranges[0][END] = db->ranges[0][START];
+
+ /* Get the letter */
+ SKIPWHITE (s);
+ switch (*s)
+ {
+ case 'a':
+ type = ADD;
+ break;
+ case 'c':
+ type = CHANGE;
+ break;
+ case 'd':
+ type = DELETE;
+ break;
+ default:
+ return ERROR; /* Bad format */
+ }
+ s++; /* Past letter */
+
+ /* Read second set of digits */
+ SKIPWHITE (s);
+ READNUM (s, db->ranges[1][START]);
+
+ /* Was that the only digit? */
+ SKIPWHITE (s);
+ if (*s == ',')
+ {
+ /* Get the next digit */
+ s++;
+ READNUM (s, db->ranges[1][END]);
+ SKIPWHITE (s); /* To move to end */
+ }
+ else
+ db->ranges[1][END] = db->ranges[1][START];
+
+ *string = s;
+ return type;
+}
+
+static char *
+read_diff (filea, fileb, output_placement)
+ char *filea, *fileb;
+ char **output_placement;
+{
+ char *argv[7];
+ char horizon_arg[256];
+ char **ap;
+ int fds[2];
+ char *diff_result;
+ int current_chunk_size;
+ int bytes;
+ int total;
+ int pid, w;
+ int wstatus;
+
+ ap = argv;
+ *ap++ = diff_program;
+ if (always_text)
+ *ap++ = "-a";
+ sprintf (horizon_arg, "--horizon-lines=%d", horizon_lines);
+ *ap++ = horizon_arg;
+ *ap++ = "--";
+ *ap++ = filea;
+ *ap++ = fileb;
+ *ap = (char *) 0;
+
+ if (pipe (fds) < 0)
+ perror_with_exit ("pipe failed");
+
+ pid = vfork ();
+ if (pid == 0)
+ {
+ /* Child */
+ close (fds[0]);
+ if (fds[1] != fileno (stdout))
+ {
+ dup2 (fds[1], fileno (stdout));
+ close (fds[1]);
+ }
+ execve (diff_program, argv, environ);
+ /* Avoid stdio, because the parent process's buffers are inherited. */
+ write (fileno (stderr), diff_program, strlen (diff_program));
+ write (fileno (stderr), ": not found\n", 12);
+ _exit (2);
+ }
+
+ if (pid == -1)
+ perror_with_exit ("fork failed");
+
+ close (fds[1]); /* Prevent erroneous lack of EOF */
+ current_chunk_size = DIFF_CHUNK_SIZE;
+ diff_result = (char *) xmalloc (current_chunk_size);
+ total = 0;
+ do {
+ bytes = myread (fds[0],
+ diff_result + total,
+ current_chunk_size - total);
+ total += bytes;
+ if (total == current_chunk_size)
+ diff_result = (char *) xrealloc (diff_result, (current_chunk_size *= 2));
+ } while (bytes);
+
+ if (total != 0 && diff_result[total-1] != '\n')
+ fatal ("invalid diff format; incomplete last line");
+
+ *output_placement = diff_result;
+
+ do
+ if ((w = wait (&wstatus)) == -1)
+ perror_with_exit ("wait failed");
+ while (w != pid);
+
+ if (! (WIFEXITED (wstatus) && WEXITSTATUS (wstatus) < 2))
+ fatal ("subsidiary diff failed");
+
+ return diff_result + total;
+}
+
+
+/*
+ * Scan a regular diff line (consisting of > or <, followed by a
+ * space, followed by text (including nulls) up to a newline.
+ *
+ * This next routine began life as a macro and many parameters in it
+ * are used as call-by-reference values.
+ */
+static char *
+scan_diff_line (scan_ptr, set_start, set_length, limit, firstchar)
+ char *scan_ptr, **set_start;
+ int *set_length;
+ char *limit;
+ char firstchar;
+{
+ char *line_ptr;
+
+ if (!(scan_ptr[0] == (firstchar)
+ && scan_ptr[1] == ' '))
+ fatal ("invalid diff format; incorrect leading line chars");
+
+ *set_start = line_ptr = scan_ptr + 2;
+ while (*line_ptr++ != '\n')
+ ;
+
+ /* Include newline if the original line ended in a newline,
+ or if an edit script is being generated.
+ Copy any missing newline message to stderr if an edit script is being
+ generated, because edit scripts cannot handle missing newlines.
+ Return the beginning of the next line. */
+ *set_length = line_ptr - *set_start;
+ if (line_ptr < limit && *line_ptr == '\\')
+ {
+ if (edscript)
+ fprintf (stderr, "%s:", argv0);
+ else
+ --*set_length;
+ line_ptr++;
+ do
+ {
+ if (edscript)
+ putc (*line_ptr, stderr);
+ }
+ while (*line_ptr++ != '\n');
+ }
+
+ return line_ptr;
+}
+
+/*
+ * This routine outputs a three way diff passed as a list of
+ * diff3_block's.
+ * The argument MAPPING is indexed by external file number (in the
+ * argument list) and contains the internal file number (from the
+ * diff passed). This is important because the user expects his
+ * outputs in terms of the argument list number, and the diff passed
+ * may have been done slightly differently (if the last argument
+ * was "-", for example).
+ * REV_MAPPING is the inverse of MAPPING.
+ */
+static void
+output_diff3 (outputfile, diff, mapping, rev_mapping)
+ FILE *outputfile;
+ struct diff3_block *diff;
+ int mapping[3], rev_mapping[3];
+{
+ int i;
+ int oddoneout;
+ char *cp;
+ struct diff3_block *ptr;
+ int line;
+ int length;
+ int dontprint;
+ static int skew_increment[3] = { 2, 3, 1 }; /* 0==>2==>1==>3 */
+
+ for (ptr = diff; ptr; ptr = D_NEXT (ptr))
+ {
+ char x[2];
+
+ switch (ptr->correspond)
+ {
+ case DIFF_ALL:
+ x[0] = '\0';
+ dontprint = 3; /* Print them all */
+ oddoneout = 3; /* Nobody's odder than anyone else */
+ break;
+ case DIFF_1ST:
+ case DIFF_2ND:
+ case DIFF_3RD:
+ oddoneout = rev_mapping[(int) ptr->correspond - (int) DIFF_1ST];
+
+ x[0] = oddoneout + '1';
+ x[1] = '\0';
+ dontprint = oddoneout==0;
+ break;
+ default:
+ fatal ("internal error: invalid diff type passed to output");
+ }
+ fprintf (outputfile, "====%s\n", x);
+
+ /* Go 0, 2, 1 if the first and third outputs are equivalent. */
+ for (i = 0; i < 3;
+ i = (oddoneout == 1 ? skew_increment[i] : i + 1))
+ {
+ int realfile = mapping[i];
+ int
+ lowt = D_LOWLINE (ptr, realfile),
+ hight = D_HIGHLINE (ptr, realfile);
+
+ fprintf (outputfile, "%d:", i + 1);
+ switch (lowt - hight)
+ {
+ case 1:
+ fprintf (outputfile, "%da\n", lowt - 1);
+ break;
+ case 0:
+ fprintf (outputfile, "%dc\n", lowt);
+ break;
+ default:
+ fprintf (outputfile, "%d,%dc\n", lowt, hight);
+ break;
+ }
+
+ if (i == dontprint) continue;
+
+ for (line = 0; line < hight - lowt + 1; line++)
+ {
+ fprintf (outputfile, " ");
+ cp = D_RELNUM (ptr, realfile, line);
+ length = D_RELLEN (ptr, realfile, line);
+ fwrite (cp, sizeof (char), length, outputfile);
+ }
+ if (line != 0 && cp[length - 1] != '\n')
+ fprintf (outputfile, "\n\\ No newline at end of file\n");
+ }
+ }
+}
+
+
+/*
+ * Output to OUTPUTFILE the lines of B taken from FILENUM.
+ * Double any initial '.'s; yield nonzero if any initial '.'s were doubled.
+ */
+static int
+dotlines (outputfile, b, filenum)
+ FILE *outputfile;
+ struct diff3_block *b;
+ int filenum;
+{
+ int i;
+ int leading_dot = 0;
+
+ for (i = 0;
+ i < D_NUMLINES (b, filenum);
+ i++)
+ {
+ char *line = D_RELNUM (b, filenum, i);
+ if (line[0] == '.')
+ {
+ leading_dot = 1;
+ fprintf (outputfile, ".");
+ }
+ fwrite (line, sizeof (char),
+ D_RELLEN (b, filenum, i), outputfile);
+ }
+
+ return leading_dot;
+}
+
+/*
+ * Output to OUTPUTFILE a '.' line. If LEADING_DOT is nonzero,
+ * also output a command that removes initial '.'s
+ * starting with line START and continuing for NUM lines.
+ */
+static void
+undotlines (outputfile, leading_dot, start, num)
+ FILE *outputfile;
+ int leading_dot, start, num;
+{
+ fprintf (outputfile, ".\n");
+ if (leading_dot)
+ if (num == 1)
+ fprintf (outputfile, "%ds/^\\.//\n", start);
+ else
+ fprintf (outputfile, "%d,%ds/^\\.//\n", start, start + num - 1);
+}
+
+/*
+ * This routine outputs a diff3 set of blocks as an ed script. This
+ * script applies the changes between file's 2 & 3 to file 1. It
+ * takes the precise format of the ed script to be output from global
+ * variables set during options processing. Note that it does
+ * destructive things to the set of diff3 blocks it is passed; it
+ * reverses their order (this gets around the problems involved with
+ * changing line numbers in an ed script).
+ *
+ * Note that this routine has the same problem of mapping as the last
+ * one did; the variable MAPPING maps from file number according to
+ * the argument list to file number according to the diff passed. All
+ * files listed below are in terms of the argument list.
+ * REV_MAPPING is the inverse of MAPPING.
+ *
+ * The arguments FILE0, FILE1 and FILE2 are the strings to print
+ * as the names of the three files. These may be the actual names,
+ * or may be the arguments specified with -L.
+ *
+ * Returns 1 if conflicts were found.
+ */
+
+static int
+output_diff3_edscript (outputfile, diff, mapping, rev_mapping,
+ file0, file1, file2)
+ FILE *outputfile;
+ struct diff3_block *diff;
+ int mapping[3], rev_mapping[3];
+ char *file0, *file1, *file2;
+{
+ int leading_dot;
+ int conflicts_found = 0, conflict;
+ struct diff3_block *b;
+
+ for (b = reverse_diff3_blocklist (diff); b; b = b->next)
+ {
+ /* Must do mapping correctly. */
+ enum diff_type type
+ = ((b->correspond == DIFF_ALL) ?
+ DIFF_ALL :
+ ((enum diff_type)
+ (((int) DIFF_1ST)
+ + rev_mapping[(int) b->correspond - (int) DIFF_1ST])));
+
+ /* If we aren't supposed to do this output block, skip it. */
+ switch (type)
+ {
+ default: continue;
+ case DIFF_2ND: if (!show_2nd) continue; conflict = 1; break;
+ case DIFF_3RD: if (overlap_only) continue; conflict = 0; break;
+ case DIFF_ALL: if (simple_only) continue; conflict = flagging; break;
+ }
+
+ if (conflict)
+ {
+ conflicts_found = 1;
+
+
+ /* Mark end of conflict. */
+
+ fprintf (outputfile, "%da\n", D_HIGHLINE (b, mapping[FILE0]));
+ leading_dot = 0;
+ if (type == DIFF_ALL)
+ {
+ if (show_2nd)
+ {
+ /* Append lines from FILE1. */
+ fprintf (outputfile, "||||||| %s\n", file1);
+ leading_dot = dotlines (outputfile, b, mapping[FILE1]);
+ }
+ /* Append lines from FILE2. */
+ fprintf (outputfile, "=======\n");
+ leading_dot |= dotlines (outputfile, b, mapping[FILE2]);
+ }
+ fprintf (outputfile, ">>>>>>> %s\n", file2);
+ undotlines (outputfile, leading_dot,
+ D_HIGHLINE (b, mapping[FILE0]) + 2,
+ (D_NUMLINES (b, mapping[FILE1])
+ + D_NUMLINES (b, mapping[FILE2]) + 1));
+
+
+ /* Mark start of conflict. */
+
+ fprintf (outputfile, "%da\n<<<<<<< %s\n",
+ D_LOWLINE (b, mapping[FILE0]) - 1,
+ type == DIFF_ALL ? file0 : file1);
+ leading_dot = 0;
+ if (type == DIFF_2ND)
+ {
+ /* Prepend lines from FILE1. */
+ leading_dot = dotlines (outputfile, b, mapping[FILE1]);
+ fprintf (outputfile, "=======\n");
+ }
+ undotlines (outputfile, leading_dot,
+ D_LOWLINE (b, mapping[FILE0]) + 1,
+ D_NUMLINES (b, mapping[FILE1]));
+ }
+ else if (D_NUMLINES (b, mapping[FILE2]) == 0)
+ /* Write out a delete */
+ {
+ if (D_NUMLINES (b, mapping[FILE0]) == 1)
+ fprintf (outputfile, "%dd\n",
+ D_LOWLINE (b, mapping[FILE0]));
+ else
+ fprintf (outputfile, "%d,%dd\n",
+ D_LOWLINE (b, mapping[FILE0]),
+ D_HIGHLINE (b, mapping[FILE0]));
+ }
+ else
+ /* Write out an add or change */
+ {
+ switch (D_NUMLINES (b, mapping[FILE0]))
+ {
+ case 0:
+ fprintf (outputfile, "%da\n",
+ D_HIGHLINE (b, mapping[FILE0]));
+ break;
+ case 1:
+ fprintf (outputfile, "%dc\n",
+ D_HIGHLINE (b, mapping[FILE0]));
+ break;
+ default:
+ fprintf (outputfile, "%d,%dc\n",
+ D_LOWLINE (b, mapping[FILE0]),
+ D_HIGHLINE (b, mapping[FILE0]));
+ break;
+ }
+
+ undotlines (outputfile, dotlines (outputfile, b, mapping[FILE2]),
+ D_LOWLINE (b, mapping[FILE0]),
+ D_NUMLINES (b, mapping[FILE2]));
+ }
+ }
+ if (finalwrite) fprintf (outputfile, "w\nq\n");
+ return conflicts_found;
+}
+
+/*
+ * Read from INFILE and output to OUTPUTFILE a set of diff3_ blocks DIFF
+ * as a merged file. This acts like 'ed file0 <[output_diff3_edscript]',
+ * except that it works even for binary data or incomplete lines.
+ *
+ * As before, MAPPING maps from arg list file number to diff file number,
+ * REV_MAPPING is its inverse,
+ * and FILE0, FILE1, and FILE2 are the names of the files.
+ *
+ * Returns 1 if conflicts were found.
+ */
+
+static int
+output_diff3_merge (infile, outputfile, diff, mapping, rev_mapping,
+ file0, file1, file2)
+ FILE *infile, *outputfile;
+ struct diff3_block *diff;
+ int mapping[3], rev_mapping[3];
+ char *file0, *file1, *file2;
+{
+ int c, i;
+ int conflicts_found = 0, conflict;
+ struct diff3_block *b;
+ int linesread = 0;
+
+ for (b = diff; b; b = b->next)
+ {
+ /* Must do mapping correctly. */
+ enum diff_type type
+ = ((b->correspond == DIFF_ALL) ?
+ DIFF_ALL :
+ ((enum diff_type)
+ (((int) DIFF_1ST)
+ + rev_mapping[(int) b->correspond - (int) DIFF_1ST])));
+ char *format_2nd = "<<<<<<< %s\n";
+
+ /* If we aren't supposed to do this output block, skip it. */
+ switch (type)
+ {
+ default: continue;
+ case DIFF_2ND: if (!show_2nd) continue; conflict = 1; break;
+ case DIFF_3RD: if (overlap_only) continue; conflict = 0; break;
+ case DIFF_ALL: if (simple_only) continue; conflict = flagging;
+ format_2nd = "||||||| %s\n";
+ break;
+ }
+
+ /* Copy I lines from file 0. */
+ i = D_LOWLINE (b, FILE0) - linesread - 1;
+ linesread += i;
+ while (0 <= --i)
+ do
+ {
+ c = getc (infile);
+ if (c == EOF)
+ if (ferror (infile))
+ perror_with_exit ("input file");
+ else if (feof (infile))
+ fatal ("input file shrank");
+ putc (c, outputfile);
+ }
+ while (c != '\n');
+
+ if (conflict)
+ {
+ conflicts_found = 1;
+
+ if (type == DIFF_ALL)
+ {
+ /* Put in lines from FILE0 with bracket. */
+ fprintf (outputfile, "<<<<<<< %s\n", file0);
+ for (i = 0;
+ i < D_NUMLINES (b, mapping[FILE0]);
+ i++)
+ fwrite (D_RELNUM (b, mapping[FILE0], i), sizeof (char),
+ D_RELLEN (b, mapping[FILE0], i), outputfile);
+ }
+
+ if (show_2nd)
+ {
+ /* Put in lines from FILE1 with bracket. */
+ fprintf (outputfile, format_2nd, file1);
+ for (i = 0;
+ i < D_NUMLINES (b, mapping[FILE1]);
+ i++)
+ fwrite (D_RELNUM (b, mapping[FILE1], i), sizeof (char),
+ D_RELLEN (b, mapping[FILE1], i), outputfile);
+ }
+
+ fprintf (outputfile, "=======\n");
+ }
+
+ /* Put in lines from FILE2. */
+ for (i = 0;
+ i < D_NUMLINES (b, mapping[FILE2]);
+ i++)
+ fwrite (D_RELNUM (b, mapping[FILE2], i), sizeof (char),
+ D_RELLEN (b, mapping[FILE2], i), outputfile);
+
+ if (conflict)
+ fprintf (outputfile, ">>>>>>> %s\n", file2);
+
+ /* Skip I lines in file 0. */
+ i = D_NUMLINES (b, FILE0);
+ linesread += i;
+ while (0 <= --i)
+ while ((c = getc (infile)) != '\n')
+ if (c == EOF)
+ if (ferror (infile))
+ perror_with_exit ("input file");
+ else if (feof (infile))
+ {
+ if (i || b->next)
+ fatal ("input file shrank");
+ return conflicts_found;
+ }
+ }
+ /* Copy rest of common file. */
+ while ((c = getc (infile)) != EOF || !(ferror (infile) | feof (infile)))
+ putc (c, outputfile);
+ return conflicts_found;
+}
+
+/*
+ * Reverse the order of the list of diff3 blocks.
+ */
+static struct diff3_block *
+reverse_diff3_blocklist (diff)
+ struct diff3_block *diff;
+{
+ register struct diff3_block *tmp, *next, *prev;
+
+ for (tmp = diff, prev = (struct diff3_block *) 0;
+ tmp; tmp = next)
+ {
+ next = tmp->next;
+ tmp->next = prev;
+ prev = tmp;
+ }
+
+ return prev;
+}
+\f
+static int
+myread (fd, ptr, size)
+ int fd, size;
+ char *ptr;
+{
+ int result = read (fd, ptr, size);
+ if (result < 0)
+ perror_with_exit ("read failed");
+ return result;
+}
+\f
+VOID *
+xmalloc (size)
+ unsigned size;
+{
+ VOID *result = (VOID *) malloc (size ? size : 1);
+ if (!result)
+ fatal ("virtual memory exhausted");
+ return result;
+}
+
+static VOID *
+xrealloc (ptr, size)
+ VOID *ptr;
+ unsigned size;
+{
+ VOID *result = (VOID *) realloc (ptr, size ? size : 1);
+ if (!result)
+ fatal ("virtual memory exhausted");
+ return result;
+}
+\f
+static void
+fatal (string)
+ char *string;
+{
+ fprintf (stderr, "%s: %s\n", argv0, string);
+ exit (2);
+}
+
+static void
+perror_with_exit (string)
+ char *string;
+{
+ int e = errno;
+ fprintf (stderr, "%s: ", argv0);
+ errno = e;
+ perror (string);
+ exit (2);
+}
projects / unix-history / commitdiff