3 Copyright (C) 1997, 1998, 2002, 2004 Free Software Foundation, Inc.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2, or (at your option)
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software Foundation,
17 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
22 /* FIXME: this is small for testing */
23 #define BUFFER_SIZE (8)
25 #define LEN(X, I) ((X)->p[(I)].one_past_end - (X)->p[(I)].start)
26 #define EMPTY(X) ((X)->n_bufs == 1 && LEN (X, 0) == 0)
28 #define ONE_PAST_END(X, I) ((X)->p[(I)].one_past_end)
35 typedef struct Line_ptr Line_ptr;
49 typedef struct Buf Buf;
52 buf_init_from_stdin (Buf *x, char eol_byte)
54 bool last_byte_is_eol_byte = true;
57 #define OBS (&(x->obs))
62 char *buf = (char *) malloc (BUFFER_SIZE);
67 /* Fall back on the code that relies on a temporary file.
68 Write all buffers to that file and free them. */
73 bytes_read = full_read (STDIN_FILENO, buf, BUFFER_SIZE);
74 if (bytes_read != buffer_size && errno != 0)
75 error (EXIT_FAILURE, errno, _("read error"));
80 bp.one_past_end = buf + bytes_read;
81 obstack_grow (OBS, &bp, sizeof (bp));
85 last_byte_is_eol_byte = (buf[bytes_read - 1] == eol_byte);
87 if (bytes_read < BUFFER_SIZE)
93 /* If the file was non-empty and lacked an EOL_BYTE at its end,
94 then add a buffer containing just that one byte. */
95 if (!last_byte_is_eol_byte)
97 char *buf = malloc (1);
100 /* FIXME: just like above */
108 bp.one_past_end = buf + 1;
109 obstack_grow (OBS, &bp, sizeof (bp));
114 x->n_bufs = obstack_object_size (OBS) / sizeof (x->p[0]);
115 x->p = (struct B_pair *) obstack_finish (OBS);
117 /* If there are two or more buffers and the last buffer is empty,
118 then free the last one and decrement the buffer count. */
120 && x->p[x->n_bufs - 1].start == x->p[x->n_bufs - 1].one_past_end)
121 free (x->p[--(x->n_bufs)].start);
130 for (i = 0; i < x->n_bufs; i++)
131 free (x->p[i].start);
132 obstack_free (OBS, NULL);
136 line_ptr_decrement (const Buf *x, const Line_ptr *lp)
140 if (lp->ptr > x->p[lp->i].start)
143 lp_new.ptr = lp->ptr - 1;
148 lp_new.i = lp->i - 1;
149 lp_new.ptr = ONE_PAST_END (x, lp->i - 1) - 1;
155 line_ptr_increment (const Buf *x, const Line_ptr *lp)
159 assert (lp->ptr <= ONE_PAST_END (x, lp->i) - 1);
160 if (lp->ptr < ONE_PAST_END (x, lp->i) - 1)
163 lp_new.ptr = lp->ptr + 1;
167 assert (lp->i < x->n_bufs - 1);
168 lp_new.i = lp->i + 1;
169 lp_new.ptr = x->p[lp->i + 1].start;
175 find_bol (const Buf *x,
176 const Line_ptr *last_bol, Line_ptr *new_bol, char eol_byte)
182 if (last_bol->ptr == x->p[0].start)
185 tmp = line_ptr_decrement (x, last_bol);
186 last_bol_ptr = tmp.ptr;
190 char *nl = memrchr (x->p[i].start, last_bol_ptr, eol_byte);
196 *new_bol = line_ptr_increment (x, &nl_pos);
204 last_bol_ptr = ONE_PAST_END (x, i);
207 /* If last_bol->ptr didn't point at the first byte of X, then reaching
208 this point means that we're about to return the line that is at the
210 if (last_bol->ptr != x->p[0].start)
213 new_bol->ptr = x->p[0].start;
221 print_line (FILE *out_stream, const Buf *x,
222 const Line_ptr *bol, const Line_ptr *bol_next)
225 for (i = bol->i; i <= bol_next->i; i++)
227 char *a = (i == bol->i ? bol->ptr : x->p[i].start);
228 char *b = (i == bol_next->i ? bol_next->ptr : ONE_PAST_END (x, i));
229 fwrite (a, 1, b - a, out_stream);
238 char eol_byte = '\n';
240 if (! buf_init_from_stdin (&x, eol_byte))
246 /* Special case the empty file. */
250 /* Initially, point at one past the last byte of the file. */
251 bol.i = x.n_bufs - 1;
252 bol.ptr = ONE_PAST_END (&x, bol.i);
257 if (! find_bol (&x, &bol, &new_bol, eol_byte))
259 print_line (stdout, &x, &new_bol, &bol);