4 /* FIXME: this is small for testing */
5 #define BUFFER_SIZE (8)
7 #define LEN(X, I) ((X)->p[(I)].one_past_end - (X)->p[(I)].start)
8 #define EMPTY(X) ((X)->n_bufs == 1 && LEN (X, 0) == 0)
10 #define ONE_PAST_END(X, I) ((X)->p[(I)].one_past_end)
17 typedef struct Line_ptr Line_ptr;
31 typedef struct Buf Buf;
34 buf_init_from_stdin (Buf *x, char eol_byte)
36 bool last_byte_is_eol_byte = true;
39 #define OBS (&(x->obs))
44 char *buf = (char *) malloc (BUFFER_SIZE);
49 /* Fall back on the code that relies on a temporary file.
50 Write all buffers to that file and free them. */
55 bytes_read = full_read (STDIN_FILENO, buf, BUFFER_SIZE);
56 if (bytes_read != buffer_size && errno != 0)
57 error (EXIT_FAILURE, errno, _("read error"));
62 bp.one_past_end = buf + bytes_read;
63 obstack_grow (OBS, &bp, sizeof (bp));
67 last_byte_is_eol_byte = (buf[bytes_read - 1] == eol_byte);
69 if (bytes_read < BUFFER_SIZE)
75 /* If the file was non-empty and lacked an EOL_BYTE at its end,
76 then add a buffer containing just that one byte. */
77 if (!last_byte_is_eol_byte)
79 char *buf = malloc (1);
82 /* FIXME: just like above */
90 bp.one_past_end = buf + 1;
91 obstack_grow (OBS, &bp, sizeof (bp));
96 x->n_bufs = obstack_object_size (OBS) / sizeof (x->p[0]);
97 x->p = (struct B_pair *) obstack_finish (OBS);
99 /* If there are two or more buffers and the last buffer is empty,
100 then free the last one and decrement the buffer count. */
102 && x->p[x->n_bufs - 1].start == x->p[x->n_bufs - 1].one_past_end)
103 free (x->p[--(x->n_bufs)].start);
112 for (i = 0; i < x->n_bufs; i++)
113 free (x->p[i].start);
114 obstack_free (OBS, NULL);
118 line_ptr_decrement (const Buf *x, const Line_ptr *lp)
122 if (lp->ptr > x->p[lp->i].start)
125 lp_new.ptr = lp->ptr - 1;
130 lp_new.i = lp->i - 1;
131 lp_new.ptr = ONE_PAST_END (x, lp->i - 1) - 1;
137 line_ptr_increment (const Buf *x, const Line_ptr *lp)
141 assert (lp->ptr <= ONE_PAST_END (x, lp->i) - 1);
142 if (lp->ptr < ONE_PAST_END (x, lp->i) - 1)
145 lp_new.ptr = lp->ptr + 1;
149 assert (lp->i < x->n_bufs - 1);
150 lp_new.i = lp->i + 1;
151 lp_new.ptr = x->p[lp->i + 1].start;
157 find_bol (const Buf *x,
158 const Line_ptr *last_bol, Line_ptr *new_bol, char eol_byte)
164 if (last_bol->ptr == x->p[0].start)
167 tmp = line_ptr_decrement (x, last_bol);
168 last_bol_ptr = tmp.ptr;
172 char *nl = memrchr (x->p[i].start, last_bol_ptr, eol_byte);
178 *new_bol = line_ptr_increment (x, &nl_pos);
186 last_bol_ptr = ONE_PAST_END (x, i);
189 /* If last_bol->ptr didn't point at the first byte of X, then reaching
190 this point means that we're about to return the line that is at the
192 if (last_bol->ptr != x->p[0].start)
195 new_bol->ptr = x->p[0].start;
203 print_line (FILE *out_stream, const Buf *x,
204 const Line_ptr *bol, const Line_ptr *bol_next)
207 for (i = bol->i; i <= bol_next->i; i++)
209 char *a = (i == bol->i ? bol->ptr : x->p[i].start);
210 char *b = (i == bol_next->i ? bol_next->ptr : ONE_PAST_END (x, i));
211 fwrite (a, 1, b - a, out_stream);
220 char eol_byte = '\n';
222 if (! buf_init_from_stdin (&x, eol_byte))
228 /* Special case the empty file. */
232 /* Initially, point at one past the last byte of the file. */
233 bol.i = x.n_bufs - 1;
234 bol.ptr = ONE_PAST_END (&x, bol.i);
239 if (! find_bol (&x, &bol, &new_bol, eol_byte))
241 print_line (stdout, &x, &new_bol, &bol);