--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/miscellany/patch-2.0.12u8/pch.c	Mon Apr 18 23:46:02 2005 +0900
@@ -0,0 +1,1308 @@
+/* $Header$
+ *
+ * $Log$
+ * Revision 1.1  2005/04/18 14:46:05  kono
+ * Initial revision
+ *
+ * Revision 2.0.2.0  90/05/01  22:17:51  davison
+ * patch12u: unidiff support added
+ *
+ * Revision 2.0.1.7  88/06/03  15:13:28  lwall
+ * patch10: Can now find patches in shar scripts.
+ * patch10: Hunks that swapped and then swapped back could core dump.
+ * 
+ * Revision 2.0.1.6  87/06/04  16:18:13  lwall
+ * pch_swap didn't swap p_bfake and p_efake.
+ * 
+ * Revision 2.0.1.5  87/01/30  22:47:42  lwall
+ * Improved responses to mangled patches.
+ * 
+ * Revision 2.0.1.4  87/01/05  16:59:53  lwall
+ * New-style context diffs caused double call to free().
+ * 
+ * Revision 2.0.1.3  86/11/14  10:08:33  lwall
+ * Fixed problem where a long pattern wouldn't grow the hunk.
+ * Also restored p_input_line when backtracking so error messages are right.
+ * 
+ * Revision 2.0.1.2  86/11/03  17:49:52  lwall
+ * New-style delete triggers spurious assertion error.
+ * 
+ * Revision 2.0.1.1  86/10/29  15:52:08  lwall
+ * Could falsely report new-style context diff.
+ * 
+ * Revision 2.0  86/09/17  15:39:37  lwall
+ * Baseline for netwide release.
+ * 
+ */
+
+#include "EXTERN.h"
+#include "common.h"
+#include "util.h"
+#include "INTERN.h"
+#include "pch.h"
+
+/* Patch (diff listing) abstract type. */
+
+static long p_filesize;			/* size of the patch file */
+static LINENUM p_first;			/* 1st line number */
+static LINENUM p_newfirst;		/* 1st line number of replacement */
+static LINENUM p_ptrn_lines;		/* # lines in pattern */
+static LINENUM p_repl_lines;		/* # lines in replacement text */
+static LINENUM p_end = -1;		/* last line in hunk */
+static LINENUM p_max;			/* max allowed value of p_end */
+static LINENUM p_context = 3;		/* # of context lines */
+static LINENUM p_input_line = 0;	/* current line # from patch file */
+static char **p_line = Null(char**);	/* the text of the hunk */
+static short *p_len = Null(short*);	/* length of each line */
+static char *p_char = Nullch;		/* +, -, and ! */
+static int hunkmax = INITHUNKMAX;	/* size of above arrays to begin with */
+static int p_indent;			/* indent to patch */
+static LINENUM p_base;			/* where to intuit this time */
+static LINENUM p_bline;			/* line # of p_base */
+static LINENUM p_start;			/* where intuit found a patch */
+static LINENUM p_sline;			/* and the line number for it */
+static LINENUM p_hunk_beg;		/* line number of current hunk */
+static LINENUM p_efake = -1;		/* end of faked up lines--don't free */
+static LINENUM p_bfake = -1;		/* beg of faked up lines */
+
+/* Prepare to look for the next patch in the patch file. */
+
+void
+re_patch()
+{
+    p_first = Nulline;
+    p_newfirst = Nulline;
+    p_ptrn_lines = Nulline;
+    p_repl_lines = Nulline;
+    p_end = (LINENUM)-1;
+    p_max = Nulline;
+    p_indent = 0;
+}
+
+/* Open the patch file at the beginning of time. */
+
+void
+open_patch_file(filename)
+char *filename;
+{
+    if (filename == Nullch || !*filename || strEQ(filename, "-")) {
+	pfp = fopen(TMPPATNAME, "w");
+	if (pfp == Nullfp)
+	    pfatal2("can't create %s", TMPPATNAME);
+	while (fgets(buf, sizeof buf, stdin) != Nullch)
+	    fputs(buf, pfp);
+	Fclose(pfp);
+	filename = TMPPATNAME;
+    }
+    pfp = fopen(filename, "r");
+    if (pfp == Nullfp)
+	pfatal2("patch file %s not found", filename);
+    Fstat(fileno(pfp), &filestat);
+    p_filesize = filestat.st_size;
+    next_intuit_at(0L,1L);			/* start at the beginning */
+    set_hunkmax();
+}
+
+/* Make sure our dynamically realloced tables are malloced to begin with. */
+
+void
+set_hunkmax()
+{
+#ifndef lint
+    if (p_line == Null(char**))
+	p_line = (char**) malloc((MEM)hunkmax * sizeof(char *));
+    if (p_len == Null(short*))
+	p_len  = (short*) malloc((MEM)hunkmax * sizeof(short));
+#endif
+    if (p_char == Nullch)
+	p_char = (char*)  malloc((MEM)hunkmax * sizeof(char));
+}
+
+/* Enlarge the arrays containing the current hunk of patch. */
+
+void
+grow_hunkmax()
+{
+    hunkmax *= 2;
+    /* 
+     * Note that on most systems, only the p_line array ever gets fresh memory
+     * since p_len can move into p_line's old space, and p_char can move into
+     * p_len's old space.  Not on PDP-11's however.  But it doesn't matter.
+     */
+    assert(p_line != Null(char**) && p_len != Null(short*) && p_char != Nullch);
+#ifndef lint
+    p_line = (char**) realloc((char*)p_line, (MEM)hunkmax * sizeof(char *));
+    p_len  = (short*) realloc((char*)p_len,  (MEM)hunkmax * sizeof(short));
+    p_char = (char*)  realloc((char*)p_char, (MEM)hunkmax * sizeof(char));
+#endif
+    if (p_line != Null(char**) && p_len != Null(short*) && p_char != Nullch)
+	return;
+    if (!using_plan_a)
+	fatal1("out of memory\n");
+    out_of_mem = TRUE;		/* whatever is null will be allocated again */
+				/* from within plan_a(), of all places */
+}
+
+/* True if the remainder of the patch file contains a diff of some sort. */
+
+bool
+there_is_another_patch()
+{
+    if (p_base != 0L && p_base >= p_filesize) {
+	if (verbose)
+	    say1("done\n");
+	return FALSE;
+    }
+    if (verbose)
+	say1("Hmm...");
+    diff_type = intuit_diff_type();
+    if (!diff_type) {
+	if (p_base != 0L) {
+	    if (verbose)
+		say1("  Ignoring the trailing garbage.\ndone\n");
+	}
+	else
+	    say1("  I can't seem to find a patch in there anywhere.\n");
+	return FALSE;
+    }
+    if (verbose)
+	say3("  %sooks like %s to me...\n",
+	    (p_base == 0L ? "L" : "The next patch l"),
+	    diff_type == UNI_DIFF ? "a unified diff" :
+	    diff_type == CONTEXT_DIFF ? "a context diff" :
+	    diff_type == NEW_CONTEXT_DIFF ? "a new-style context diff" :
+	    diff_type == NORMAL_DIFF ? "a normal diff" :
+	    "an ed script" );
+    if (p_indent && verbose)
+	say3("(Patch is indented %d space%s.)\n", p_indent, p_indent==1?"":"s");
+    skip_to(p_start,p_sline);
+    while (filearg[0] == Nullch) {
+	if (force || batch) {
+	    say1("No file to patch.  Skipping...\n");
+	    filearg[0] = savestr(bestguess);
+	    return TRUE;
+	}
+	ask1("File to patch: ");
+	if (*buf != '\n') {
+	    if (bestguess)
+		free(bestguess);
+	    bestguess = savestr(buf);
+	    filearg[0] = fetchname(buf, 0, FALSE);
+	}
+	if (filearg[0] == Nullch) {
+	    ask1("No file found--skip this patch? [n] ");
+	    if (*buf != 'y') {
+		continue;
+	    }
+	    if (verbose)
+		say1("Skipping patch...\n");
+	    filearg[0] = fetchname(bestguess, 0, TRUE);
+	    skip_rest_of_patch = TRUE;
+	    return TRUE;
+	}
+    }
+    return TRUE;
+}
+
+/* Determine what kind of diff is in the remaining part of the patch file. */
+
+int
+intuit_diff_type()
+{
+    Reg4 long this_line = 0;
+    Reg5 long previous_line;
+    Reg6 long first_command_line = -1;
+    long fcl_line;
+    Reg7 bool last_line_was_command = FALSE;
+    Reg8 bool this_is_a_command = FALSE;
+    Reg9 bool stars_last_line = FALSE;
+    Reg10 bool stars_this_line = FALSE;
+    Reg3 int indent;
+    Reg1 char *s;
+    Reg2 char *t;
+    char *indtmp = Nullch;
+    char *oldtmp = Nullch;
+    char *newtmp = Nullch;
+    char *indname = Nullch;
+    char *oldname = Nullch;
+    char *newname = Nullch;
+    Reg11 int retval;
+    bool no_filearg = (filearg[0] == Nullch);
+
+    ok_to_create_file = FALSE;
+    Fseek(pfp, p_base, 0);
+    p_input_line = p_bline - 1;
+    for (;;) {
+	previous_line = this_line;
+	last_line_was_command = this_is_a_command;
+	stars_last_line = stars_this_line;
+	this_line = ftell(pfp);
+	indent = 0;
+	p_input_line++;
+	if (fgets(buf, sizeof buf, pfp) == Nullch) {
+	    if (first_command_line >= 0L) {
+					/* nothing but deletes!? */
+		p_start = first_command_line;
+		p_sline = fcl_line;
+		retval = ED_DIFF;
+		goto scan_exit;
+	    }
+	    else {
+		p_start = this_line;
+		p_sline = p_input_line;
+		retval = 0;
+		goto scan_exit;
+	    }
+	}
+	for (s = buf; *s == ' ' || *s == '\t' || *s == 'X'; s++) {
+	    if (*s == '\t')
+		indent += 8 - (indent % 8);
+	    else
+		indent++;
+	}
+	for (t=s; isdigit(*t) || *t == ','; t++) ; 
+	this_is_a_command = (isdigit(*s) &&
+	  (*t == 'd' || *t == 'c' || *t == 'a') );
+	if (first_command_line < 0L && this_is_a_command) { 
+	    first_command_line = this_line;
+	    fcl_line = p_input_line;
+	    p_indent = indent;		/* assume this for now */
+	}
+	if (!stars_last_line && strnEQ(s, "*** ", 4))
+	    oldtmp = savestr(s+4);
+	else if (strnEQ(s, "--- ", 4))
+	    newtmp = savestr(s+4);
+	else if (strnEQ(s, "+++ ", 4))
+	    oldtmp = savestr(s+4);	/* pretend it is the old name */
+	else if (strnEQ(s, "Index:", 6))
+	    indtmp = savestr(s+6);
+	else if (strnEQ(s, "Prereq:", 7)) {
+	    for (t=s+7; isspace(*t); t++) ;
+	    revision = savestr(t);
+	    for (t=revision; *t && !isspace(*t); t++) ;
+	    *t = '\0';
+	    if (!*revision) {
+		free(revision);
+		revision = Nullch;
+	    }
+	}
+	if ((!diff_type || diff_type == ED_DIFF) &&
+	  first_command_line >= 0L &&
+	  strEQ(s, ".\n") ) {
+	    p_indent = indent;
+	    p_start = first_command_line;
+	    p_sline = fcl_line;
+	    retval = ED_DIFF;
+	    goto scan_exit;
+	}
+	if ((!diff_type || diff_type == UNI_DIFF) && strnEQ(s, "@@ -", 4)) {
+	    if (!atol(s+3))
+		ok_to_create_file = TRUE;
+	    p_indent = indent;
+	    p_start = this_line;
+	    p_sline = p_input_line;
+	    retval = UNI_DIFF;
+	    goto scan_exit;
+	}
+	stars_this_line = strnEQ(s, "********", 8);
+	if ((!diff_type || diff_type == CONTEXT_DIFF) && stars_last_line &&
+		 strnEQ(s, "*** ", 4)) {
+	    if (!atol(s+4))
+		ok_to_create_file = TRUE;
+	    /* if this is a new context diff the character just before */
+	    /* the newline is a '*'. */
+	    while (*s != '\n')
+		s++;
+	    p_indent = indent;
+	    p_start = previous_line;
+	    p_sline = p_input_line - 1;
+	    retval = (*(s-1) == '*' ? NEW_CONTEXT_DIFF : CONTEXT_DIFF);
+	    goto scan_exit;
+	}
+	if ((!diff_type || diff_type == NORMAL_DIFF) && 
+	  last_line_was_command &&
+	  (strnEQ(s, "< ", 2) || strnEQ(s, "> ", 2)) ) {
+	    p_start = previous_line;
+	    p_sline = p_input_line - 1;
+	    p_indent = indent;
+	    retval = NORMAL_DIFF;
+	    goto scan_exit;
+	}
+    }
+  scan_exit:
+    if (no_filearg) {
+	if (indtmp != Nullch)
+	    indname = fetchname(indtmp, strippath, ok_to_create_file);
+	if (oldtmp != Nullch)
+	    oldname = fetchname(oldtmp, strippath, ok_to_create_file);
+	if (newtmp != Nullch)
+	    newname = fetchname(newtmp, strippath, ok_to_create_file);
+	if (oldname && newname) {
+	    if (strlen(oldname) < strlen(newname))
+		filearg[0] = savestr(oldname);
+	    else
+		filearg[0] = savestr(newname);
+	}
+	else if (oldname)
+	    filearg[0] = savestr(oldname);
+	else if (newname)
+	    filearg[0] = savestr(newname);
+	else if (indname)
+	    filearg[0] = savestr(indname);
+    }
+    if (bestguess) {
+	free(bestguess);
+	bestguess = Nullch;
+    }
+    if (filearg[0] != Nullch)
+	bestguess = savestr(filearg[0]);
+    else if (indtmp != Nullch)
+	bestguess = fetchname(indtmp, strippath, TRUE);
+    else {
+	if (oldtmp != Nullch)
+	    oldname = fetchname(oldtmp, strippath, TRUE);
+	if (newtmp != Nullch)
+	    newname = fetchname(newtmp, strippath, TRUE);
+	if (oldname && newname) {
+	    if (strlen(oldname) < strlen(newname))
+		bestguess = savestr(oldname);
+	    else
+		bestguess = savestr(newname);
+	}
+	else if (oldname)
+	    bestguess = savestr(oldname);
+	else if (newname)
+	    bestguess = savestr(newname);
+    }
+    if (indtmp != Nullch)
+	free(indtmp);
+    if (oldtmp != Nullch)
+	free(oldtmp);
+    if (newtmp != Nullch)
+	free(newtmp);
+    if (indname != Nullch)
+	free(indname);
+    if (oldname != Nullch)
+	free(oldname);
+    if (newname != Nullch)
+	free(newname);
+    return retval;
+}
+
+/* Remember where this patch ends so we know where to start up again. */
+
+void
+next_intuit_at(file_pos,file_line)
+long file_pos;
+long file_line;
+{
+    p_base = file_pos;
+    p_bline = file_line;
+}
+
+/* Basically a verbose fseek() to the actual diff listing. */
+
+void
+skip_to(file_pos,file_line)
+long file_pos;
+long file_line;
+{
+    char *ret;
+
+    assert(p_base <= file_pos);
+    if (verbose && p_base < file_pos) {
+	Fseek(pfp, p_base, 0);
+	say1("The text leading up to this was:\n--------------------------\n");
+	while (ftell(pfp) < file_pos) {
+	    ret = fgets(buf, sizeof buf, pfp);
+	    assert(ret != Nullch);
+	    say2("|%s", buf);
+	}
+	say1("--------------------------\n");
+    }
+    else
+	Fseek(pfp, file_pos, 0);
+    p_input_line = file_line - 1;
+}
+
+/* Make this a function for better debugging.  */
+static void
+malformed ()
+{
+    fatal3("malformed patch at line %ld: %s", p_input_line, buf);
+		/* about as informative as "Syntax error" in C */
+}
+
+/* True if there is more of the current diff listing to process. */
+
+bool
+another_hunk()
+{
+    Reg1 char *s;
+    Reg8 char *ret;
+    Reg2 int context = 0;
+
+    while (p_end >= 0) {
+	if (p_end == p_efake)
+	    p_end = p_bfake;		/* don't free twice */
+	else
+	    free(p_line[p_end]);
+	p_end--;
+    }
+    assert(p_end == -1);
+    p_efake = -1;
+
+    p_max = hunkmax;			/* gets reduced when --- found */
+    if (diff_type == CONTEXT_DIFF || diff_type == NEW_CONTEXT_DIFF) {
+	long line_beginning = ftell(pfp);
+					/* file pos of the current line */
+	LINENUM repl_beginning = 0;	/* index of --- line */
+	Reg4 LINENUM fillcnt = 0;	/* #lines of missing ptrn or repl */
+	Reg5 LINENUM fillsrc;		/* index of first line to copy */
+	Reg6 LINENUM filldst;		/* index of first missing line */
+	bool ptrn_spaces_eaten = FALSE;	/* ptrn was slightly misformed */
+	Reg9 bool repl_could_be_missing = TRUE;
+					/* no + or ! lines in this hunk */
+	bool repl_missing = FALSE;	/* we are now backtracking */
+	long repl_backtrack_position = 0;
+					/* file pos of first repl line */
+	LINENUM repl_patch_line;	/* input line number for same */
+	Reg7 LINENUM ptrn_copiable = 0;
+					/* # of copiable lines in ptrn */
+
+	ret = pgets(buf, sizeof buf, pfp);
+	p_input_line++;
+	if (ret == Nullch || strnNE(buf, "********", 8)) {
+	    next_intuit_at(line_beginning,p_input_line);
+	    return FALSE;
+	}
+	p_context = 100;
+	p_hunk_beg = p_input_line + 1;
+	while (p_end < p_max) {
+	    line_beginning = ftell(pfp);
+	    ret = pgets(buf, sizeof buf, pfp);
+	    p_input_line++;
+	    if (ret == Nullch) {
+		if (p_max - p_end < 4)
+		    Strcpy(buf, "  \n");  /* assume blank lines got chopped */
+		else {
+		    if (repl_beginning && repl_could_be_missing) {
+			repl_missing = TRUE;
+			goto hunk_done;
+		    }
+		    fatal1("unexpected end of file in patch\n");
+		}
+	    }
+	    p_end++;
+	    assert(p_end < hunkmax);
+	    p_char[p_end] = *buf;
+#ifdef zilog
+	    p_line[(short)p_end] = Nullch;
+#else
+	    p_line[p_end] = Nullch;
+#endif
+	    switch (*buf) {
+	    case '*':
+		if (strnEQ(buf, "********", 8)) {
+		    if (repl_beginning && repl_could_be_missing) {
+			repl_missing = TRUE;
+			goto hunk_done;
+		    }
+		    else
+			fatal2("unexpected end of hunk at line %ld\n",
+			    p_input_line);
+		}
+		if (p_end != 0) {
+		    if (repl_beginning && repl_could_be_missing) {
+			repl_missing = TRUE;
+			goto hunk_done;
+		    }
+		    fatal3("unexpected *** at line %ld: %s", p_input_line, buf);
+		}
+		context = 0;
+		p_line[p_end] = savestr(buf);
+		if (out_of_mem) {
+		    p_end--;
+		    return FALSE;
+		}
+		for (s=buf; *s && !isdigit(*s); s++) ;
+		if (!*s)
+		    malformed ();
+		if (strnEQ(s,"0,0",3))
+		    strcpy(s,s+2);
+		p_first = (LINENUM) atol(s);
+		while (isdigit(*s)) s++;
+		if (*s == ',') {
+		    for (; *s && !isdigit(*s); s++) ;
+		    if (!*s)
+			malformed ();
+		    p_ptrn_lines = ((LINENUM)atol(s)) - p_first + 1;
+		}
+		else if (p_first)
+		    p_ptrn_lines = 1;
+		else {
+		    p_ptrn_lines = 0;
+		    p_first = 1;
+		}
+		p_max = p_ptrn_lines + 6;	/* we need this much at least */
+		while (p_max >= hunkmax)
+		    grow_hunkmax();
+		p_max = hunkmax;
+		break;
+	    case '-':
+		if (buf[1] == '-') {
+		    if (repl_beginning ||
+			(p_end != p_ptrn_lines + 1 + (p_char[p_end-1] == '\n')))
+		    {
+			if (p_end == 1) {
+			    /* `old' lines were omitted - set up to fill */
+			    /* them in from 'new' context lines. */
+			    p_end = p_ptrn_lines + 1;
+			    fillsrc = p_end + 1;
+			    filldst = 1;
+			    fillcnt = p_ptrn_lines;
+			}
+			else {
+			    if (repl_beginning) {
+				if (repl_could_be_missing){
+				    repl_missing = TRUE;
+				    goto hunk_done;
+				}
+				fatal3(
+"duplicate \"---\" at line %ld--check line numbers at line %ld\n",
+				    p_input_line, p_hunk_beg + repl_beginning);
+			    }
+			    else {
+				fatal4(
+"%s \"---\" at line %ld--check line numbers at line %ld\n",
+				    (p_end <= p_ptrn_lines
+					? "Premature"
+					: "Overdue" ),
+				    p_input_line, p_hunk_beg);
+			    }
+			}
+		    }
+		    repl_beginning = p_end;
+		    repl_backtrack_position = ftell(pfp);
+		    repl_patch_line = p_input_line;
+		    p_line[p_end] = savestr(buf);
+		    if (out_of_mem) {
+			p_end--;
+			return FALSE;
+		    }
+		    p_char[p_end] = '=';
+		    for (s=buf; *s && !isdigit(*s); s++) ;
+		    if (!*s)
+			malformed ();
+		    p_newfirst = (LINENUM) atol(s);
+		    while (isdigit(*s)) s++;
+		    if (*s == ',') {
+			for (; *s && !isdigit(*s); s++) ;
+			if (!*s)
+			    malformed ();
+			p_repl_lines = ((LINENUM)atol(s)) - p_newfirst + 1;
+		    }
+		    else if (p_newfirst)
+			p_repl_lines = 1;
+		    else {
+			p_repl_lines = 0;
+			p_newfirst = 1;
+		    }
+		    p_max = p_repl_lines + p_end;
+		    if (p_max > MAXHUNKSIZE)
+			fatal4("hunk too large (%ld lines) at line %ld: %s",
+			      p_max, p_input_line, buf);
+		    while (p_max >= hunkmax)
+			grow_hunkmax();
+		    if (p_repl_lines != ptrn_copiable
+		     && (p_context != 0 || p_repl_lines != 1))
+			repl_could_be_missing = FALSE;
+		    break;
+		}
+		goto change_line;
+	    case '+':  case '!':
+		repl_could_be_missing = FALSE;
+	      change_line:
+		if (buf[1] == '\n' && canonicalize)
+		    strcpy(buf+1," \n");
+		if (!isspace(buf[1]) && buf[1] != '>' && buf[1] != '<' &&
+		  repl_beginning && repl_could_be_missing) {
+		    repl_missing = TRUE;
+		    goto hunk_done;
+		}
+		if (context >= 0) {
+		    if (context < p_context)
+			p_context = context;
+		    context = -1000;
+		}
+		p_line[p_end] = savestr(buf+2);
+		if (out_of_mem) {
+		    p_end--;
+		    return FALSE;
+		}
+		break;
+	    case '\t': case '\n':	/* assume the 2 spaces got eaten */
+		if (repl_beginning && repl_could_be_missing &&
+		  (!ptrn_spaces_eaten || diff_type == NEW_CONTEXT_DIFF) ) {
+		    repl_missing = TRUE;
+		    goto hunk_done;
+		}
+		p_line[p_end] = savestr(buf);
+		if (out_of_mem) {
+		    p_end--;
+		    return FALSE;
+		}
+		if (p_end != p_ptrn_lines + 1) {
+		    ptrn_spaces_eaten |= (repl_beginning != 0);
+		    context++;
+		    if (!repl_beginning)
+			ptrn_copiable++;
+		    p_char[p_end] = ' ';
+		}
+		break;
+	    case ' ':
+		if (!isspace(buf[1]) &&
+		  repl_beginning && repl_could_be_missing) {
+		    repl_missing = TRUE;
+		    goto hunk_done;
+		}
+		context++;
+		if (!repl_beginning)
+		    ptrn_copiable++;
+		p_line[p_end] = savestr(buf+2);
+		if (out_of_mem) {
+		    p_end--;
+		    return FALSE;
+		}
+		break;
+	    default:
+		if (repl_beginning && repl_could_be_missing) {
+		    repl_missing = TRUE;
+		    goto hunk_done;
+		}
+		malformed ();
+	    }
+	    /* set up p_len for strncmp() so we don't have to */
+	    /* assume null termination */
+	    if (p_line[p_end])
+		p_len[p_end] = strlen(p_line[p_end]);
+	    else
+		p_len[p_end] = 0;
+	}
+	
+    hunk_done:
+	if (p_end >=0 && !repl_beginning)
+	    fatal2("no --- found in patch at line %ld\n", pch_hunk_beg());
+
+	if (repl_missing) {
+	    
+	    /* reset state back to just after --- */
+	    p_input_line = repl_patch_line;
+	    for (p_end--; p_end > repl_beginning; p_end--)
+		free(p_line[p_end]);
+	    Fseek(pfp, repl_backtrack_position, 0);
+	    
+	    /* redundant 'new' context lines were omitted - set */
+	    /* up to fill them in from the old file context */
+	    if (!p_context && p_repl_lines == 1) {
+		p_repl_lines = 0;
+		p_max--;
+	    }
+	    fillsrc = 1;
+	    filldst = repl_beginning+1;
+	    fillcnt = p_repl_lines;
+	    p_end = p_max;
+	}
+	else if (!p_context && fillcnt == 1) {
+	    /* the first hunk was a null hunk with no context */
+	    /* and we were expecting one line -- fix it up. */
+	    while (filldst < p_end) {
+		p_line[filldst] = p_line[filldst+1];
+		p_char[filldst] = p_char[filldst+1];
+		p_len[filldst] = p_len[filldst+1];
+		filldst++;
+	    }
+#if 0
+	    repl_beginning--;		/* this doesn't need to be fixed */
+#endif
+	    p_end--;
+	    p_first++;			/* do append rather than insert */
+	    fillcnt = 0;
+	    p_ptrn_lines = 0;
+	}
+
+	if (diff_type == CONTEXT_DIFF &&
+	  (fillcnt || (p_first > 1 && ptrn_copiable > 2*p_context)) ) {
+	    if (verbose)
+		say4("%s\n%s\n%s\n",
+"(Fascinating--this is really a new-style context diff but without",
+"the telltale extra asterisks on the *** line that usually indicate",
+"the new style...)");
+	    diff_type = NEW_CONTEXT_DIFF;
+	}
+	
+	/* if there were omitted context lines, fill them in now */
+	if (fillcnt) {
+	    p_bfake = filldst;		/* remember where not to free() */
+	    p_efake = filldst + fillcnt - 1;
+	    while (fillcnt-- > 0) {
+		while (fillsrc <= p_end && p_char[fillsrc] != ' ')
+		    fillsrc++;
+		if (fillsrc > p_end)
+		    fatal2("replacement text or line numbers mangled in hunk at line %ld\n",
+			p_hunk_beg);
+		p_line[filldst] = p_line[fillsrc];
+		p_char[filldst] = p_char[fillsrc];
+		p_len[filldst] = p_len[fillsrc];
+		fillsrc++; filldst++;
+	    }
+	    while (fillsrc <= p_end && fillsrc != repl_beginning &&
+	      p_char[fillsrc] != ' ')
+		fillsrc++;
+#ifdef DEBUGGING
+	    if (debug & 64)
+		printf("fillsrc %ld, filldst %ld, rb %ld, e+1 %ld\n",
+		    fillsrc,filldst,repl_beginning,p_end+1);
+#endif
+	    assert(fillsrc==p_end+1 || fillsrc==repl_beginning);
+	    assert(filldst==p_end+1 || filldst==repl_beginning);
+	}
+    }
+    else if (diff_type == UNI_DIFF) {
+	long line_beginning = ftell(pfp);
+					/* file pos of the current line */
+	Reg4 LINENUM fillsrc;		/* index of old lines */
+	Reg5 LINENUM filldst;		/* index of new lines */
+	char ch;
+
+	ret = pgets(buf, sizeof buf, pfp);
+	p_input_line++;
+	if (ret == Nullch || strnNE(buf, "@@ -", 4)) {
+	    next_intuit_at(line_beginning,p_input_line);
+	    return FALSE;
+	}
+	s = buf+4;
+	if (!*s)
+	    malformed ();
+	p_first = (LINENUM) atol(s);
+	while (isdigit(*s)) s++;
+	if (*s == ',') {
+	    p_ptrn_lines = (LINENUM) atol(++s);
+	    while (isdigit(*s)) s++;
+	} else
+	    p_ptrn_lines = 1;
+	if (*s == ' ') s++;
+	if (*s != '+' || !*++s)
+	    malformed ();
+	p_newfirst = (LINENUM) atol(s);
+	while (isdigit(*s)) s++;
+	if (*s == ',') {
+	    p_repl_lines = (LINENUM) atol(++s);
+	    while (isdigit(*s)) s++;
+	} else
+	    p_repl_lines = 1;
+	if (*s == ' ') s++;
+	if (*s != '@')
+	    malformed ();
+	if (!p_ptrn_lines)
+	    p_first++;			/* do append rather than insert */
+	p_max = p_ptrn_lines + p_repl_lines + 1;
+	while (p_max >= hunkmax)
+	    grow_hunkmax();
+	fillsrc = 1;
+	filldst = fillsrc + p_ptrn_lines;
+	p_end = filldst + p_repl_lines;
+	Sprintf(buf,"*** %ld,%ld ****\n",p_first,p_first + p_ptrn_lines - 1);
+	p_line[0] = savestr(buf);
+	if (out_of_mem) {
+	    p_end = -1;
+	    return FALSE;
+	}
+	p_char[0] = '*';
+        Sprintf(buf,"--- %ld,%ld ----\n",p_newfirst,p_newfirst+p_repl_lines-1);
+	p_line[filldst] = savestr(buf);
+	if (out_of_mem) {
+	    p_end = 0;
+	    return FALSE;
+	}
+	p_char[filldst++] = '=';
+	p_context = 100;
+	context = 0;
+	p_hunk_beg = p_input_line + 1;
+	while (fillsrc <= p_ptrn_lines || filldst <= p_end) {
+	    line_beginning = ftell(pfp);
+	    ret = pgets(buf, sizeof buf, pfp);
+	    p_input_line++;
+	    if (ret == Nullch) {
+		if (p_max - filldst < 3)
+		    Strcpy(buf, " \n");  /* assume blank lines got chopped */
+		else {
+		    fatal1("unexpected end of file in patch\n");
+		}
+	    }
+	    if (*buf == '\t' || *buf == '\n') {
+		ch = ' ';		/* assume the space got eaten */
+		s = savestr(buf);
+	    }
+	    else {
+		ch = *buf;
+		s = savestr(buf+1);
+	    }
+	    if (out_of_mem) {
+		while (--filldst > p_ptrn_lines)
+		    free(p_line[filldst]);
+		p_end = fillsrc-1;
+		return FALSE;
+	    }
+	    switch (ch) {
+	    case '-':
+		if (fillsrc > p_ptrn_lines) {
+		    free(s);
+		    p_end = filldst-1;
+		    malformed ();
+		}
+		p_char[fillsrc] = ch;
+		p_line[fillsrc] = s;
+		p_len[fillsrc++] = strlen(s);
+		break;
+	    case '=':
+		ch = ' ';
+		/* FALL THROUGH */
+	    case ' ':
+		if (fillsrc > p_ptrn_lines) {
+		    free(s);
+		    while (--filldst > p_ptrn_lines)
+			free(p_line[filldst]);
+		    p_end = fillsrc-1;
+		    malformed ();
+		}
+		context++;
+		p_char[fillsrc] = ch;
+		p_line[fillsrc] = s;
+		p_len[fillsrc++] = strlen(s);
+		s = savestr(s);
+		if (out_of_mem) {
+		    while (--filldst > p_ptrn_lines)
+			free(p_line[filldst]);
+		    p_end = fillsrc-1;
+		    return FALSE;
+		}
+		/* FALL THROUGH */
+	    case '+':
+		if (filldst > p_end) {
+		    free(s);
+		    while (--filldst > p_ptrn_lines)
+			free(p_line[filldst]);
+		    p_end = fillsrc-1;
+		    malformed ();
+		}
+		p_char[filldst] = ch;
+		p_line[filldst] = s;
+		p_len[filldst++] = strlen(s);
+		break;
+	    default:
+		p_end = filldst;
+		malformed ();
+	    }
+	    if (ch != ' ' && context > 0) {
+		if (context < p_context)
+		    p_context = context;
+		context = -1000;
+	    }
+	}/* while */
+    }
+    else {				/* normal diff--fake it up */
+	char hunk_type;
+	Reg3 int i;
+	LINENUM min, max;
+	long line_beginning = ftell(pfp);
+
+	p_context = 0;
+	ret = pgets(buf, sizeof buf, pfp);
+	p_input_line++;
+	if (ret == Nullch || !isdigit(*buf)) {
+	    next_intuit_at(line_beginning,p_input_line);
+	    return FALSE;
+	}
+	p_first = (LINENUM)atol(buf);
+	for (s=buf; isdigit(*s); s++) ;
+	if (*s == ',') {
+	    p_ptrn_lines = (LINENUM)atol(++s) - p_first + 1;
+	    while (isdigit(*s)) s++;
+	}
+	else
+	    p_ptrn_lines = (*s != 'a');
+	hunk_type = *s;
+	if (hunk_type == 'a')
+	    p_first++;			/* do append rather than insert */
+	min = (LINENUM)atol(++s);
+	for (; isdigit(*s); s++) ;
+	if (*s == ',')
+	    max = (LINENUM)atol(++s);
+	else
+	    max = min;
+	if (hunk_type == 'd')
+	    min++;
+	p_end = p_ptrn_lines + 1 + max - min + 1;
+	if (p_end > MAXHUNKSIZE)
+	    fatal4("hunk too large (%ld lines) at line %ld: %s",
+		  p_end, p_input_line, buf);
+	while (p_end >= hunkmax)
+	    grow_hunkmax();
+	p_newfirst = min;
+	p_repl_lines = max - min + 1;
+	Sprintf(buf, "*** %ld,%ld\n", p_first, p_first + p_ptrn_lines - 1);
+	p_line[0] = savestr(buf);
+	if (out_of_mem) {
+	    p_end = -1;
+	    return FALSE;
+	}
+	p_char[0] = '*';
+	for (i=1; i<=p_ptrn_lines; i++) {
+	    ret = pgets(buf, sizeof buf, pfp);
+	    p_input_line++;
+	    if (ret == Nullch)
+		fatal2("unexpected end of file in patch at line %ld\n",
+		  p_input_line);
+	    if (*buf != '<')
+		fatal2("< expected at line %ld of patch\n", p_input_line);
+	    p_line[i] = savestr(buf+2);
+	    if (out_of_mem) {
+		p_end = i-1;
+		return FALSE;
+	    }
+	    p_len[i] = strlen(p_line[i]);
+	    p_char[i] = '-';
+	}
+	if (hunk_type == 'c') {
+	    ret = pgets(buf, sizeof buf, pfp);
+	    p_input_line++;
+	    if (ret == Nullch)
+		fatal2("unexpected end of file in patch at line %ld\n",
+		    p_input_line);
+	    if (*buf != '-')
+		fatal2("--- expected at line %ld of patch\n", p_input_line);
+	}
+	Sprintf(buf, "--- %ld,%ld\n", min, max);
+	p_line[i] = savestr(buf);
+	if (out_of_mem) {
+	    p_end = i-1;
+	    return FALSE;
+	}
+	p_char[i] = '=';
+	for (i++; i<=p_end; i++) {
+	    ret = pgets(buf, sizeof buf, pfp);
+	    p_input_line++;
+	    if (ret == Nullch)
+		fatal2("unexpected end of file in patch at line %ld\n",
+		    p_input_line);
+	    if (*buf != '>')
+		fatal2("> expected at line %ld of patch\n", p_input_line);
+	    p_line[i] = savestr(buf+2);
+	    if (out_of_mem) {
+		p_end = i-1;
+		return FALSE;
+	    }
+	    p_len[i] = strlen(p_line[i]);
+	    p_char[i] = '+';
+	}
+    }
+    if (reverse)			/* backwards patch? */
+	if (!pch_swap())
+	    say1("Not enough memory to swap next hunk!\n");
+#ifdef DEBUGGING
+    if (debug & 2) {
+	int i;
+	char special;
+
+	for (i=0; i <= p_end; i++) {
+	    if (i == p_ptrn_lines)
+		special = '^';
+	    else
+		special = ' ';
+	    fprintf(stderr, "%3d %c %c %s", i, p_char[i], special, p_line[i]);
+	    Fflush(stderr);
+	}
+    }
+#endif
+    if (p_end+1 < hunkmax)	/* paranoia reigns supreme... */
+	p_char[p_end+1] = '^';  /* add a stopper for apply_hunk */
+    return TRUE;
+}
+
+/* Input a line from the patch file, worrying about indentation. */
+
+char *
+pgets(bf,sz,fp)
+char *bf;
+int sz;
+FILE *fp;
+{
+    char *ret = fgets(bf, sz, fp);
+    Reg1 char *s;
+    Reg2 int indent = 0;
+
+    if (p_indent && ret != Nullch) {
+	for (s=buf;
+	  indent < p_indent && (*s == ' ' || *s == '\t' || *s == 'X'); s++) {
+	    if (*s == '\t')
+		indent += 8 - (indent % 7);
+	    else
+		indent++;
+	}
+	if (buf != s)
+	    Strcpy(buf, s);
+    }
+    return ret;
+}
+
+/* Reverse the old and new portions of the current hunk. */
+
+bool
+pch_swap()
+{
+    char **tp_line;		/* the text of the hunk */
+    short *tp_len;		/* length of each line */
+    char *tp_char;		/* +, -, and ! */
+    Reg1 LINENUM i;
+    Reg2 LINENUM n;
+    bool blankline = FALSE;
+    Reg3 char *s;
+
+    i = p_first;
+    p_first = p_newfirst;
+    p_newfirst = i;
+    
+    /* make a scratch copy */
+
+    tp_line = p_line;
+    tp_len = p_len;
+    tp_char = p_char;
+    p_line = Null(char**);	/* force set_hunkmax to allocate again */
+    p_len = Null(short*);
+    p_char = Nullch;
+    set_hunkmax();
+    if (p_line == Null(char**) || p_len == Null(short*) || p_char == Nullch) {
+#ifndef lint
+	if (p_line == Null(char**))
+	    free((char*)p_line);
+	p_line = tp_line;
+	if (p_len == Null(short*))
+	    free((char*)p_len);
+	p_len = tp_len;
+#endif
+	if (p_char == Nullch)
+	    free((char*)p_char);
+	p_char = tp_char;
+	return FALSE;		/* not enough memory to swap hunk! */
+    }
+
+    /* now turn the new into the old */
+
+    i = p_ptrn_lines + 1;
+    if (tp_char[i] == '\n') {		/* account for possible blank line */
+	blankline = TRUE;
+	i++;
+    }
+    if (p_efake >= 0) {			/* fix non-freeable ptr range */
+	if (p_efake <= i)
+	    n = p_end - i + 1;
+	else
+	    n = -i;
+	p_efake += n;
+	p_bfake += n;
+    }
+    for (n=0; i <= p_end; i++,n++) {
+	p_line[n] = tp_line[i];
+	p_char[n] = tp_char[i];
+	if (p_char[n] == '+')
+	    p_char[n] = '-';
+	p_len[n] = tp_len[i];
+    }
+    if (blankline) {
+	i = p_ptrn_lines + 1;
+	p_line[n] = tp_line[i];
+	p_char[n] = tp_char[i];
+	p_len[n] = tp_len[i];
+	n++;
+    }
+    assert(p_char[0] == '=');
+    p_char[0] = '*';
+    for (s=p_line[0]; *s; s++)
+	if (*s == '-')
+	    *s = '*';
+
+    /* now turn the old into the new */
+
+    assert(tp_char[0] == '*');
+    tp_char[0] = '=';
+    for (s=tp_line[0]; *s; s++)
+	if (*s == '*')
+	    *s = '-';
+    for (i=0; n <= p_end; i++,n++) {
+	p_line[n] = tp_line[i];
+	p_char[n] = tp_char[i];
+	if (p_char[n] == '-')
+	    p_char[n] = '+';
+	p_len[n] = tp_len[i];
+    }
+    assert(i == p_ptrn_lines + 1);
+    i = p_ptrn_lines;
+    p_ptrn_lines = p_repl_lines;
+    p_repl_lines = i;
+#ifndef lint
+    if (tp_line == Null(char**))
+	free((char*)tp_line);
+    if (tp_len == Null(short*))
+	free((char*)tp_len);
+#endif
+    if (tp_char == Nullch)
+	free((char*)tp_char);
+    return TRUE;
+}
+
+/* Return the specified line position in the old file of the old context. */
+
+LINENUM
+pch_first()
+{
+    return p_first;
+}
+
+/* Return the number of lines of old context. */
+
+LINENUM
+pch_ptrn_lines()
+{
+    return p_ptrn_lines;
+}
+
+/* Return the probable line position in the new file of the first line. */
+
+LINENUM
+pch_newfirst()
+{
+    return p_newfirst;
+}
+
+/* Return the number of lines in the replacement text including context. */
+
+LINENUM
+pch_repl_lines()
+{
+    return p_repl_lines;
+}
+
+/* Return the number of lines in the whole hunk. */
+
+LINENUM
+pch_end()
+{
+    return p_end;
+}
+
+/* Return the number of context lines before the first changed line. */
+
+LINENUM
+pch_context()
+{
+    return p_context;
+}
+
+/* Return the length of a particular patch line. */
+
+short
+pch_line_len(line)
+LINENUM line;
+{
+    return p_len[line];
+}
+
+/* Return the control character (+, -, *, !, etc) for a patch line. */
+
+char
+pch_char(line)
+LINENUM line;
+{
+    return p_char[line];
+}
+
+/* Return a pointer to a particular patch line. */
+
+char *
+pfetch(line)
+LINENUM line;
+{
+    return p_line[line];
+}
+
+/* Return where in the patch file this hunk began, for error messages. */
+
+LINENUM
+pch_hunk_beg()
+{
+    return p_hunk_beg;
+}
+
+/* Apply an ed script by feeding ed itself. */
+
+void
+do_ed_script()
+{
+    Reg1 char *t;
+    Reg2 long beginning_of_this_line;
+    Reg3 bool this_line_is_command = FALSE;
+    Reg4 FILE *pipefp;
+
+    if (!skip_rest_of_patch) {
+	Unlink(TMPOUTNAME);
+	copy_file(filearg[0], TMPOUTNAME);
+	if (verbose)
+	    Sprintf(buf, "/bin/ed %s", TMPOUTNAME);
+	else
+	    Sprintf(buf, "/bin/ed - %s", TMPOUTNAME);
+	pipefp = popen(buf, "w");
+    }
+    for (;;) {
+	beginning_of_this_line = ftell(pfp);
+	if (pgets(buf, sizeof buf, pfp) == Nullch) {
+	    next_intuit_at(beginning_of_this_line,p_input_line);
+	    break;
+	}
+	p_input_line++;
+	for (t=buf; isdigit(*t) || *t == ','; t++) ;
+	this_line_is_command = (isdigit(*buf) &&
+	  (*t == 'd' || *t == 'c' || *t == 'a') );
+	if (this_line_is_command) {
+	    if (!skip_rest_of_patch)
+		fputs(buf, pipefp);
+	    if (*t != 'd') {
+		while (pgets(buf, sizeof buf, pfp) != Nullch) {
+		    p_input_line++;
+		    if (!skip_rest_of_patch)
+			fputs(buf, pipefp);
+		    if (strEQ(buf, ".\n"))
+			break;
+		}
+	    }
+	}
+	else {
+	    next_intuit_at(beginning_of_this_line,p_input_line);
+	    break;
+	}
+    }
+    if (skip_rest_of_patch)
+	return;
+    fprintf(pipefp, "w\n");
+    fprintf(pipefp, "q\n");
+    Fflush(pipefp);
+    Pclose(pipefp);
+    ignore_signals();
+    if (move_file(TMPOUTNAME, outname) < 0) {
+	toutkeep = TRUE;
+	chmod(TMPOUTNAME, filemode);
+    }
+    else
+	chmod(outname, filemode);
+    set_signals(1);
+}