-/* unexpand - convert spaces to tabs
+/* unexpand - convert blanks to tabs
Copyright (C) 89, 91, 1995-2004 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
--tabs=tab1[,tab2[,...]]
-t tab1[,tab2[,...]]
-tab1[,tab2[,...]] If only one tab stop is given, set the tabs tab1
- spaces apart instead of the default 8. Otherwise,
+ columns apart instead of the default 8. Otherwise,
set the tabs at columns tab1, tab2, etc. (numbered from
- 0); replace any tabs beyond the tabstops given with
- single spaces.
+ 0); preserve any blanks beyond the tab stops given.
--all
- -a Use tabs wherever they would replace 2 or more spaces,
+ -a Use tabs wherever they would replace 2 or more blanks,
not just at the beginnings of lines.
David MacKenzie <djm@gnu.ai.mit.edu> */
allocated for the output line. */
#define OUTPUT_BLOCK 256
-/* A sentinel value that's placed at the end of the list of tab stops.
- This value must be a large number, but not so large that adding the
- length of a line to it would cause the column variable to overflow.
- FIXME: The algorithm isn't correct once the numbers get large;
- also, no error is reported if overflow occurs. */
-#define TAB_STOP_SENTINEL INTMAX_MAX
-
/* The name this program was run with. */
char *program_name;
static bool convert_entire_line;
/* If nonzero, the size of all tab stops. If zero, use `tab_list' instead. */
-static uintmax_t tab_size;
+static size_t tab_size;
+
+/* The maximum distance between tab stops. */
+static size_t max_column_width;
/* Array of the explicit column numbers of the tab stops;
after `tab_list' is exhausted, the rest of the line is printed
"),
program_name);
fputs (_("\
-Convert spaces in each FILE to tabs, writing to standard output.\n\
+Convert blanks in each FILE to tabs, writing to standard output.\n\
With no FILE, or when FILE is -, read standard input.\n\
\n\
"), stdout);
Mandatory arguments to long options are mandatory for short options too.\n\
"), stdout);
fputs (_("\
- -a, --all convert all whitespace, instead of just initial whitespace\n\
- --first-only convert only leading sequences of whitespace (overrides -a)\n\
+ -a, --all convert all blanks, instead of just initial blanks\n\
+ --first-only convert only leading sequences of blanks (overrides -a)\n\
-t, --tabs=N have tabs N characters apart instead of 8 (enables -a)\n\
-t, --tabs=LIST use comma separated LIST of tab positions (enables -a)\n\
"), stdout);
/* Add tab stop TABVAL to the end of `tab_list'. */
static void
-add_tabstop (uintmax_t tabval)
+add_tab_stop (uintmax_t tabval)
{
+ uintmax_t column_width =
+ tabval - (first_free_tab ? tab_list[first_free_tab - 1] : 0);
+
if (first_free_tab == n_tabs_allocated)
tab_list = x2nrealloc (tab_list, &n_tabs_allocated, sizeof *tab_list);
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 tabstops STOPS
- to the list of tabstops. */
+/* Add the comma or blank separated list of tab stops STOPS
+ to the list of tab stops. */
static void
-parse_tabstops (char const *stops)
+parse_tab_stops (char const *stops)
{
bool have_tabval = false;
uintmax_t tabval IF_LINT (= 0);
if (*stops == ',' || ISBLANK (to_uchar (*stops)))
{
if (have_tabval)
- add_tabstop (tabval);
+ add_tab_stop (tabval);
have_tabval = false;
}
else if (ISDIGIT (*stops))
exit (EXIT_FAILURE);
if (have_tabval)
- add_tabstop (tabval);
+ add_tab_stop (tabval);
}
-/* Check that the list of tabstops TABS, with ENTRIES entries,
+/* Check that the list of tab stops TABS, with ENTRIES entries,
contains only nonzero, ascending values. */
static void
-validate_tabstops (uintmax_t const *tabs, size_t entries)
+validate_tab_stops (uintmax_t const *tabs, size_t entries)
{
uintmax_t prev_tab = 0;
size_t i;
}
if (fp == stdin)
clearerr (fp); /* Also clear EOF. */
- else if (fclose (fp) == EOF)
+ else if (fclose (fp) != 0)
{
error (0, errno, "%s", prev_file);
exit_status = EXIT_FAILURE;
return NULL;
}
-/* Change spaces to tabs, writing to stdout.
+/* Change blanks to tabs, writing to stdout.
Read each file in `file_list', in order. */
static void
unexpand (void)
{
- FILE *fp; /* Input stream. */
- size_t tab_index = 0; /* Index in `tab_list' of next tabstop. */
- size_t print_tab_index = 0; /* For printing as many tabs as possible. */
- uintmax_t column = 0; /* Column of next char. */
- uintmax_t next_tab_column; /* Column the next tab stop is on. */
- bool convert = true; /* If true, perform translations. */
- uintmax_t pending = 0; /* Pending columns of blanks. */
- int saved_errno IF_LINT (= 0);
-
- fp = next_file ((FILE *) NULL);
- if (fp == NULL)
+ /* Input stream. */
+ FILE *fp = next_file (NULL);
+
+ /* The array of pending blanks. In non-POSIX locales, blanks can
+ include characters other than spaces, so the blanks must be
+ stored, not merely counted. */
+ char *pending_blank;
+
+ if (!fp)
return;
/* Binary I/O will preserve the original EOL style (DOS/Unix) of files. */
SET_BINARY2 (fileno (fp), STDOUT_FILENO);
+ /* The worst case is a non-blank character, then one blank, then a
+ tab stop, then MAX_COLUMN_WIDTH - 1 blanks, then a non-blank; so
+ allocate MAX_COLUMN_WIDTH bytes to store the blanks. */
+ pending_blank = xmalloc (max_column_width);
+
for (;;)
{
- int c = getc (fp);
- if (c == EOF)
- {
- fp = next_file (fp);
- if (fp)
- {
- SET_BINARY2 (fileno (fp), STDOUT_FILENO);
- continue;
- }
- saved_errno = errno;
- }
+ /* Input character, or EOF. */
+ int c;
- if (c == ' ' && convert && column < TAB_STOP_SENTINEL)
- {
- ++pending;
- ++column;
- }
- else if (c == '\t' && convert)
- {
- if (tab_size == 0)
- {
- /* Do not let tab_index == first_free_tab;
- stop when it is 1 less. */
- while (tab_index < first_free_tab - 1
- && column >= tab_list[tab_index])
- tab_index++;
- next_tab_column = tab_list[tab_index];
- if (tab_index < first_free_tab - 1)
- tab_index++;
- if (column >= next_tab_column)
- {
- convert = false; /* Ran out of tab stops. */
- goto flush_pend;
- }
- }
- else
- {
- next_tab_column = column + tab_size - column % tab_size;
- }
- pending += next_tab_column - column;
- column = next_tab_column;
- }
- else
+ /* If true, perform translations. */
+ bool convert = true;
+
+
+ /* The following variables have valid values only when CONVERT
+ is true: */
+
+ /* Column of next input character. */
+ uintmax_t column = 0;
+
+ /* Column the next input tab stop is on. */
+ uintmax_t next_tab_column = 0;
+
+ /* Index in TAB_LIST of next tab stop to examine. */
+ size_t tab_index = 0;
+
+ /* If true, the first pending blank came just before a tab stop. */
+ bool one_blank_before_tab_stop = false;
+
+ /* If true, the previous input character was a blank. This is
+ initially true, since initial strings of blanks are treated
+ as if the line was preceded by a blank. */
+ bool prev_blank = true;
+
+ /* Number of pending columns of blanks. */
+ size_t pending = 0;
+
+
+ /* Convert a line of text. */
+
+ do
{
- flush_pend:
- /* Flush pending spaces. Print as many tabs as possible,
- then print the rest as spaces. */
- if (pending == 1)
- {
- putchar (' ');
- pending = 0;
- }
- column -= pending;
- while (pending > 0)
+ while ((c = getc (fp)) < 0 && (fp = next_file (fp)))
+ SET_BINARY2 (fileno (fp), STDOUT_FILENO);
+
+ if (convert)
{
- if (tab_size == 0)
- {
- /* Do not let print_tab_index == first_free_tab;
- stop when it is 1 less. */
- while (print_tab_index < first_free_tab - 1
- && column >= tab_list[print_tab_index])
- print_tab_index++;
- next_tab_column = tab_list[print_tab_index];
- if (print_tab_index < first_free_tab - 1)
- print_tab_index++;
- }
- else
+ bool blank = ISBLANK (c);
+
+ if (blank)
{
- next_tab_column = column + tab_size - column % tab_size;
+ if (next_tab_column <= column)
+ {
+ if (tab_size)
+ next_tab_column =
+ column + (tab_size - column % tab_size);
+ else
+ for (;;)
+ if (tab_index == first_free_tab)
+ {
+ convert = false;
+ break;
+ }
+ else
+ {
+ uintmax_t tab = tab_list[tab_index++];
+ if (column < tab)
+ {
+ next_tab_column = tab;
+ break;
+ }
+ }
+ }
+
+ if (convert)
+ {
+ if (next_tab_column < column)
+ error (EXIT_FAILURE, 0, _("input line is too long"));
+
+ if (c == '\t')
+ {
+ column = next_tab_column;
+
+ /* Discard pending blanks, unless it was a single
+ blank just before the previous tab stop. */
+ if (! (pending == 1 && one_blank_before_tab_stop))
+ {
+ pending = 0;
+ one_blank_before_tab_stop = false;
+ }
+ }
+ else
+ {
+ column++;
+
+ if (! (prev_blank && column == next_tab_column))
+ {
+ /* It is not yet known whether the pending blanks
+ will be replaced by tabs. */
+ if (column == next_tab_column)
+ one_blank_before_tab_stop = true;
+ pending_blank[pending++] = c;
+ prev_blank = true;
+ continue;
+ }
+
+ /* Replace the pending blanks by a tab or two. */
+ pending_blank[0] = c = '\t';
+ pending = one_blank_before_tab_stop;
+ }
+ }
}
- if (next_tab_column - column <= pending)
+ else if (c == '\b')
{
- putchar ('\t');
- pending -= next_tab_column - column;
- column = next_tab_column;
+ /* Go back one column, and force recalculation of the
+ next tab stop. */
+ column -= !!column;
+ next_tab_column = column;
+ tab_index -= !!tab_index;
}
else
{
- --print_tab_index;
- column += pending;
- while (pending != 0)
- {
- putchar (' ');
- pending--;
- }
+ column++;
+ if (!column)
+ error (EXIT_FAILURE, 0, _("input line is too long"));
}
- }
-
- if (c == EOF)
- {
- errno = saved_errno;
- break;
- }
- if (convert)
- {
- if (c == '\b')
+ if (pending)
{
- if (column > 0)
- --column;
- }
- else
- {
- ++column;
- convert &= convert_entire_line;
+ if (fwrite (pending_blank, 1, pending, stdout) != pending)
+ error (EXIT_FAILURE, errno, _("write error"));
+ pending = 0;
+ one_blank_before_tab_stop = false;
}
+
+ prev_blank = blank;
+ convert &= convert_entire_line | blank;
}
- putchar (c);
-
- if (c == '\n')
+ if (c < 0)
{
- tab_index = print_tab_index = 0;
- column = pending = 0;
- convert = true;
+ free (pending_blank);
+ return;
}
+
+ if (putchar (c) < 0)
+ error (EXIT_FAILURE, errno, _("write error"));
}
+ while (c != '\n');
}
}
int c;
/* If true, cancel the effect of any -a (explicit or implicit in -t),
- so that only leading white space will be considered. */
+ so that only leading blanks will be considered. */
bool convert_first_only = false;
bool obsolete_tablist = false;
break;
case 't':
convert_entire_line = true;
- parse_tabstops (optarg);
+ parse_tab_stops (optarg);
break;
case CONVERT_FIRST_ONLY_OPTION:
convert_first_only = true;
break;
case ',':
if (have_tabval)
- add_tabstop (tabval);
+ add_tab_stop (tabval);
have_tabval = false;
obsolete_tablist = true;
break;
convert_entire_line = false;
if (have_tabval)
- add_tabstop (tabval);
+ add_tab_stop (tabval);
- validate_tabstops (tab_list, first_free_tab);
+ validate_tab_stops (tab_list, first_free_tab);
if (first_free_tab == 0)
- tab_size = 8;
+ tab_size = max_column_width = 8;
else if (first_free_tab == 1)
tab_size = tab_list[0];
else
- {
- /* Append a sentinel to the list of tab stop indices. */
- add_tabstop (TAB_STOP_SENTINEL);
- tab_size = 0;
- }
+ tab_size = 0;
file_list = (optind < argc ? &argv[optind] : stdin_argv);
unexpand ();
- if (have_read_stdin && fclose (stdin) == EOF)
+ if (have_read_stdin && fclose (stdin) != 0)
error (EXIT_FAILURE, errno, "-");
exit (exit_status);
projects / thirdparty / coreutils.git / commitdiff
