xref: /plan9/sys/src/ape/cmd/diff/ed.c (revision 0b459c2cb92b7c9d88818e9a2f72e678e5bc4553)
1 /* Output routines for ed-script format.
2    Copyright (C) 1988, 89, 91, 92, 93 Free Software Foundation, Inc.
3 
4 This file is part of GNU DIFF.
5 
6 GNU DIFF is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
9 any later version.
10 
11 GNU DIFF is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 GNU General Public License for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GNU DIFF; see the file COPYING.  If not, write to
18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
19 
20 #include "diff.h"
21 
22 static void print_ed_hunk PARAMS((struct change *));
23 static void print_rcs_hunk PARAMS((struct change *));
24 static void pr_forward_ed_hunk PARAMS((struct change *));
25 
26 /* Print our script as ed commands.  */
27 
28 void
print_ed_script(script)29 print_ed_script (script)
30     struct change *script;
31 {
32   print_script (script, find_reverse_change, print_ed_hunk);
33 }
34 
35 /* Print a hunk of an ed diff */
36 
37 static void
print_ed_hunk(hunk)38 print_ed_hunk (hunk)
39      struct change *hunk;
40 {
41   int f0, l0, f1, l1;
42   int deletes, inserts;
43 
44 #if 0
45   hunk = flip_script (hunk);
46 #endif
47 #ifdef DEBUG
48   debug_script (hunk);
49 #endif
50 
51   /* Determine range of line numbers involved in each file.  */
52   analyze_hunk (hunk, &f0, &l0, &f1, &l1, &deletes, &inserts);
53   if (!deletes && !inserts)
54     return;
55 
56   begin_output ();
57 
58   /* Print out the line number header for this hunk */
59   print_number_range (',', &files[0], f0, l0);
60   fprintf (outfile, "%c\n", change_letter (inserts, deletes));
61 
62   /* Print new/changed lines from second file, if needed */
63   if (inserts)
64     {
65       int i;
66       int inserting = 1;
67       for (i = f1; i <= l1; i++)
68 	{
69 	  /* Resume the insert, if we stopped.  */
70 	  if (! inserting)
71 	    fprintf (outfile, "%da\n",
72 		     i - f1 + translate_line_number (&files[0], f0) - 1);
73 	  inserting = 1;
74 
75 	  /* If the file's line is just a dot, it would confuse `ed'.
76 	     So output it with a double dot, and set the flag LEADING_DOT
77 	     so that we will output another ed-command later
78 	     to change the double dot into a single dot.  */
79 
80 	  if (files[1].linbuf[i][0] == '.'
81 	      && files[1].linbuf[i][1] == '\n')
82 	    {
83 	      fprintf (outfile, "..\n");
84 	      fprintf (outfile, ".\n");
85 	      /* Now change that double dot to the desired single dot.  */
86 	      fprintf (outfile, "%ds/^\\.\\././\n",
87 		       i - f1 + translate_line_number (&files[0], f0));
88 	      inserting = 0;
89 	    }
90 	  else
91 	    /* Line is not `.', so output it unmodified.  */
92 	    print_1_line ("", &files[1].linbuf[i]);
93 	}
94 
95       /* End insert mode, if we are still in it.  */
96       if (inserting)
97 	fprintf (outfile, ".\n");
98     }
99 }
100 
101 /* Print change script in the style of ed commands,
102    but print the changes in the order they appear in the input files,
103    which means that the commands are not truly useful with ed.  */
104 
105 void
pr_forward_ed_script(script)106 pr_forward_ed_script (script)
107      struct change *script;
108 {
109   print_script (script, find_change, pr_forward_ed_hunk);
110 }
111 
112 static void
pr_forward_ed_hunk(hunk)113 pr_forward_ed_hunk (hunk)
114      struct change *hunk;
115 {
116   int i;
117   int f0, l0, f1, l1;
118   int deletes, inserts;
119 
120   /* Determine range of line numbers involved in each file.  */
121   analyze_hunk (hunk, &f0, &l0, &f1, &l1, &deletes, &inserts);
122   if (!deletes && !inserts)
123     return;
124 
125   begin_output ();
126 
127   fprintf (outfile, "%c", change_letter (inserts, deletes));
128   print_number_range (' ', files, f0, l0);
129   fprintf (outfile, "\n");
130 
131   /* If deletion only, print just the number range.  */
132 
133   if (!inserts)
134     return;
135 
136   /* For insertion (with or without deletion), print the number range
137      and the lines from file 2.  */
138 
139   for (i = f1; i <= l1; i++)
140     print_1_line ("", &files[1].linbuf[i]);
141 
142   fprintf (outfile, ".\n");
143 }
144 
145 /* Print in a format somewhat like ed commands
146    except that each insert command states the number of lines it inserts.
147    This format is used for RCS.  */
148 
149 void
print_rcs_script(script)150 print_rcs_script (script)
151      struct change *script;
152 {
153   print_script (script, find_change, print_rcs_hunk);
154 }
155 
156 /* Print a hunk of an RCS diff */
157 
158 static void
print_rcs_hunk(hunk)159 print_rcs_hunk (hunk)
160      struct change *hunk;
161 {
162   int i;
163   int f0, l0, f1, l1;
164   int deletes, inserts;
165   int tf0, tl0, tf1, tl1;
166 
167   /* Determine range of line numbers involved in each file.  */
168   analyze_hunk (hunk, &f0, &l0, &f1, &l1, &deletes, &inserts);
169   if (!deletes && !inserts)
170     return;
171 
172   begin_output ();
173 
174   translate_range (&files[0], f0, l0, &tf0, &tl0);
175 
176   if (deletes)
177     {
178       fprintf (outfile, "d");
179       /* For deletion, print just the starting line number from file 0
180 	 and the number of lines deleted.  */
181       fprintf (outfile, "%d %d\n",
182 	       tf0,
183 	       (tl0 >= tf0 ? tl0 - tf0 + 1 : 1));
184     }
185 
186   if (inserts)
187     {
188       fprintf (outfile, "a");
189 
190       /* Take last-line-number from file 0 and # lines from file 1.  */
191       translate_range (&files[1], f1, l1, &tf1, &tl1);
192       fprintf (outfile, "%d %d\n",
193 	       tl0,
194 	       (tl1 >= tf1 ? tl1 - tf1 + 1 : 1));
195 
196       /* Print the inserted lines.  */
197       for (i = f1; i <= l1; i++)
198 	print_1_line ("", &files[1].linbuf[i]);
199     }
200 }
201