xref: /dragonfly/contrib/diffutils/src/ed.c (revision e0eb7cf0)
1 /* Output routines for ed-script format.
2 
3    Copyright (C) 1988-1989, 1991-1993, 1995, 1998, 2001, 2004, 2006, 2009-2013,
4    2015-2018 Free Software Foundation, Inc.
5 
6    This file is part of GNU DIFF.
7 
8    This program is free software: you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation, either version 3 of the License, or
11    (at your option) any later version.
12 
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
20 
21 #include "diff.h"
22 
23 static void print_ed_hunk (struct change *);
24 static void print_rcs_hunk (struct change *);
25 static void pr_forward_ed_hunk (struct change *);
26 
27 /* Print our script as ed commands.  */
28 
29 void
30 print_ed_script (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
38 print_ed_hunk (struct change *hunk)
39 {
40   lin f0, l0, f1, l1;
41   enum changes changes;
42 
43 #ifdef DEBUG
44   debug_script (hunk);
45 #endif
46 
47   /* Determine range of line numbers involved in each file.  */
48   changes = analyze_hunk (hunk, &f0, &l0, &f1, &l1);
49   if (!changes)
50     return;
51 
52   begin_output ();
53 
54   /* Print out the line number header for this hunk */
55   print_number_range (',', &files[0], f0, l0);
56   fputc (change_letter[changes], outfile);
57   fputc ('\n', outfile);
58 
59   /* Print new/changed lines from second file, if needed */
60   if (changes != OLD)
61     {
62       lin i;
63       bool insert_mode = true;
64 
65       for (i = f1; i <= l1; i++)
66 	{
67 	  if (!insert_mode)
68 	    {
69 	      fputs ("a\n", outfile);
70 	      insert_mode = true;
71 	    }
72 	  if (files[1].linbuf[i][0] == '.' && files[1].linbuf[i][1] == '\n')
73 	    {
74 	      /* The file's line is just a dot, and it would exit
75 		 insert mode.  Precede the dot with another dot, exit
76 		 insert mode and remove the extra dot.  */
77 	      fputs ("..\n.\ns/.//\n", outfile);
78 	      insert_mode = false;
79 	    }
80 	  else
81 	    print_1_line ("", &files[1].linbuf[i]);
82 	}
83 
84       if (insert_mode)
85 	fputs (".\n", outfile);
86     }
87 }
88 
89 /* Print change script in the style of ed commands,
90    but print the changes in the order they appear in the input files,
91    which means that the commands are not truly useful with ed.
92    Because of the issue with lines containing just a dot, the output
93    is not even parseable.  */
94 
95 void
96 pr_forward_ed_script (struct change *script)
97 {
98   print_script (script, find_change, pr_forward_ed_hunk);
99 }
100 
101 static void
102 pr_forward_ed_hunk (struct change *hunk)
103 {
104   lin i, f0, l0, f1, l1;
105 
106   /* Determine range of line numbers involved in each file.  */
107   enum changes changes = analyze_hunk (hunk, &f0, &l0, &f1, &l1);
108   if (!changes)
109     return;
110 
111   begin_output ();
112 
113   fputc (change_letter[changes], outfile);
114   print_number_range (' ', files, f0, l0);
115   fputc ('\n', outfile);
116 
117   /* If deletion only, print just the number range.  */
118 
119   if (changes == OLD)
120     return;
121 
122   /* For insertion (with or without deletion), print the number range
123      and the lines from file 2.  */
124 
125   for (i = f1; i <= l1; i++)
126     print_1_line ("", &files[1].linbuf[i]);
127 
128   fputs (".\n", outfile);
129 }
130 
131 /* Print in a format somewhat like ed commands
132    except that each insert command states the number of lines it inserts.
133    This format is used for RCS.  */
134 
135 void
136 print_rcs_script (struct change *script)
137 {
138   print_script (script, find_change, print_rcs_hunk);
139 }
140 
141 /* Print a hunk of an RCS diff */
142 
143 static void
144 print_rcs_hunk (struct change *hunk)
145 {
146   lin i, f0, l0, f1, l1;
147   printint tf0, tl0, tf1, tl1;
148 
149   /* Determine range of line numbers involved in each file.  */
150   enum changes changes = analyze_hunk (hunk, &f0, &l0, &f1, &l1);
151   if (!changes)
152     return;
153 
154   begin_output ();
155 
156   translate_range (&files[0], f0, l0, &tf0, &tl0);
157 
158   if (changes & OLD)
159     {
160       /* For deletion, print just the starting line number from file 0
161 	 and the number of lines deleted.  */
162       fprintf (outfile, "d%"pI"d %"pI"d\n", tf0,
163 	       tf0 <= tl0 ? tl0 - tf0 + 1 : 1);
164     }
165 
166   if (changes & NEW)
167     {
168       /* Take last-line-number from file 0 and # lines from file 1.  */
169       translate_range (&files[1], f1, l1, &tf1, &tl1);
170       fprintf (outfile, "a%"pI"d %"pI"d\n", tl0,
171 	       tf1 <= tl1 ? tl1 - tf1 + 1 : 1);
172 
173       /* Print the inserted lines.  */
174       for (i = f1; i <= l1; i++)
175 	print_1_line ("", &files[1].linbuf[i]);
176     }
177 }
178