summaryrefslogtreecommitdiff
path: root/src/expand-common.c
blob: 41d7003a42de6ee7c567855f6e45e109b77b8440 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
/* expand-common - common functionality for expand/unexapnd
   Copyright (C) 1989-2016 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 3 of the License, 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, see <http://www.gnu.org/licenses/>.  */

#include <config.h>

#include <stdio.h>
#include <sys/types.h>
#include "system.h"
#include "error.h"
#include "fadvise.h"
#include "quote.h"
#include "xstrndup.h"

#include "expand-common.h"

/* If true, convert blanks even after nonblank characters have been
   read on the line.  */
bool convert_entire_line = false;

/* If nonzero, the size of all tab stops.  If zero, use 'tab_list' instead.  */
static uintmax_t tab_size = 0;

/* The maximum distance between tab stops.  */
size_t max_column_width;

/* Array of the explicit column numbers of the tab stops;
   after 'tab_list' is exhausted, each additional tab is replaced
   by a space.  The first column is column 0.  */
static uintmax_t *tab_list = NULL;

/* The number of allocated entries in 'tab_list'.  */
static size_t n_tabs_allocated = 0;

/* The index of the first invalid element of 'tab_list',
   where the next element can be added.  */
static size_t first_free_tab = 0;

/* Null-terminated array of input filenames.  */
static char **file_list = NULL;

/* Default for 'file_list' if no files are given on the command line.  */
static char *stdin_argv[] =
{
  (char *) "-", NULL
};

/* True if we have ever read standard input.  */
static bool have_read_stdin = false;

/* The desired exit status.  */
int exit_status = EXIT_SUCCESS;



/* Add tab stop TABVAL to the end of 'tab_list'.  */
extern void
add_tab_stop (uintmax_t tabval)
{
  uintmax_t prev_column = first_free_tab ? tab_list[first_free_tab - 1] : 0;
  uintmax_t column_width = prev_column <= tabval ? tabval - prev_column : 0;

  if (first_free_tab == n_tabs_allocated)
    tab_list = X2NREALLOC (tab_list, &n_tabs_allocated);
  tab_list[first_free_tab++] = tabval;

  if (max_column_width < column_width)
    {
      if (SIZE_MAX < column_width)
        error (EXIT_FAILURE, 0, _("tabs are too far apart"));
      max_column_width = column_width;
    }
}

/* Add the comma or blank separated list of tab stops STOPS
   to the list of tab stops.  */
extern void
parse_tab_stops (char const *stops)
{
  bool have_tabval = false;
  uintmax_t tabval IF_LINT ( = 0);
  char const *num_start IF_LINT ( = NULL);
  bool ok = true;

  for (; *stops; stops++)
    {
      if (*stops == ',' || isblank (to_uchar (*stops)))
        {
          if (have_tabval)
            add_tab_stop (tabval);
          have_tabval = false;
        }
      else if (ISDIGIT (*stops))
        {
          if (!have_tabval)
            {
              tabval = 0;
              have_tabval = true;
              num_start = stops;
            }

          /* Detect overflow.  */
          if (!DECIMAL_DIGIT_ACCUMULATE (tabval, *stops - '0', uintmax_t))
            {
              size_t len = strspn (num_start, "0123456789");
              char *bad_num = xstrndup (num_start, len);
              error (0, 0, _("tab stop is too large %s"), quote (bad_num));
              free (bad_num);
              ok = false;
              stops = num_start + len - 1;
            }
        }
      else
        {
          error (0, 0, _("tab size contains invalid character(s): %s"),
                 quote (stops));
          ok = false;
          break;
        }
    }

  if (!ok)
    exit (EXIT_FAILURE);

  if (have_tabval)
    add_tab_stop (tabval);
}

/* Check that the list of tab stops TABS, with ENTRIES entries,
   contains only nonzero, ascending values.  */

static void
validate_tab_stops (uintmax_t const *tabs, size_t entries)
{
  uintmax_t prev_tab = 0;
  size_t i;

  for (i = 0; i < entries; i++)
    {
      if (tabs[i] == 0)
        error (EXIT_FAILURE, 0, _("tab size cannot be 0"));
      if (tabs[i] <= prev_tab)
        error (EXIT_FAILURE, 0, _("tab sizes must be ascending"));
      prev_tab = tabs[i];
    }
}

/* Called after all command-line options have been parsed,
   and add_tab_stop/parse_tab_stops have been called.
   Will validate the tab-stop values,
   and set the final values to:
   tab-stops = 8 (if no tab-stops given on command line)
   tab-stops = N (if value N specified as the only value).
   tab-stops = distinct values given on command line (if multiple values given).
*/
extern void
finalize_tab_stops (void)
{
  validate_tab_stops (tab_list, first_free_tab);

  if (first_free_tab == 0)
    tab_size = max_column_width = 8;
  else if (first_free_tab == 1)
    tab_size = tab_list[0];
  else
    tab_size = 0;
}


extern uintmax_t
get_next_tab_column (const uintmax_t column, size_t* tab_index,
                     bool* last_tab)
{
  *last_tab = false;

  /* single tab-size - return multiples of it */
  if (tab_size)
    return column + (tab_size - column % tab_size);

  /* multiple tab-sizes - iterate them until the tab position is beyond
     the current input column. */
  for ( ; *tab_index < first_free_tab ; (*tab_index)++ )
    {
        uintmax_t tab = tab_list[*tab_index];
        if (column < tab)
            return tab;
    }

  *last_tab = true;
  return 0;
}




/* Sets new file-list */
extern void
set_file_list (char **list)
{
  have_read_stdin = false;

  if (!list)
    file_list = stdin_argv;
  else
    file_list = list;
}

/* Close the old stream pointer FP if it is non-NULL,
   and return a new one opened to read the next input file.
   Open a filename of '-' as the standard input.
   Return NULL if there are no more input files.  */

extern FILE *
next_file (FILE *fp)
{
  static char *prev_file;
  char *file;

  if (fp)
    {
      if (ferror (fp))
        {
          error (0, errno, "%s", quotef (prev_file));
          exit_status = EXIT_FAILURE;
        }
      if (STREQ (prev_file, "-"))
        clearerr (fp);		/* Also clear EOF.  */
      else if (fclose (fp) != 0)
        {
          error (0, errno, "%s", quotef (prev_file));
          exit_status = EXIT_FAILURE;
        }
    }

  while ((file = *file_list++) != NULL)
    {
      if (STREQ (file, "-"))
        {
          have_read_stdin = true;
          fp = stdin;
        }
      else
        fp = fopen (file, "r");
      if (fp)
        {
          prev_file = file;
          fadvise (fp, FADVISE_SEQUENTIAL);
          return fp;
        }
      error (0, errno, "%s", quotef (file));
      exit_status = EXIT_FAILURE;
    }
  return NULL;
}

/* */
extern void
cleanup_file_list_stdin (void)
{
    if (have_read_stdin && fclose (stdin) != 0)
      error (EXIT_FAILURE, errno, "-");
}