1 /* zread - read data from file descriptor into buffer with retries */
3 /* Copyright (C) 1999-2002 Free Software Foundation, Inc.
5 This file is part of GNU Bash, the Bourne Again SHell.
7 Bash is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
12 Bash is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with Bash. If not, see <http://www.gnu.org/licenses/>.
23 #include <sys/types.h>
25 #if defined (HAVE_UNISTD_H)
39 /* Read LEN bytes from FD into BUF. Retry the read on EINTR. Any other
40 error causes the loop to break. */
49 while ((r = read (fd, buf, len)) < 0 && errno == EINTR)
54 /* Read LEN bytes from FD into BUF. Retry the read on EINTR, up to three
55 interrupts. Any other error causes the loop to break. */
63 zreadretry (fd, buf, len)
73 r = read (fd, buf, len);
76 if (r == -1 && errno == EINTR)
78 if (++nintr >= NUM_INTR)
86 /* Call read(2) and allow it to be interrupted. Just a stub for now. */
88 zreadintr (fd, buf, len)
93 return (read (fd, buf, len));
96 /* Read one character from FD and return it in CP. Return values are as
97 in read(2). This does some local buffering to avoid many one-character
98 calls to read(2), like those the `read' builtin performs. */
100 static char lbuf[128];
101 static size_t lind, lused;
110 if (lind == lused || lused == 0)
112 nr = zread (fd, lbuf, sizeof (lbuf));
126 /* Don't mix calls to zreadc and zreadcintr in the same function, since they
127 use the same local buffer. */
135 if (lind == lused || lused == 0)
137 nr = zreadintr (fd, lbuf, sizeof (lbuf));
157 /* Sync the seek pointer for FD so that the kernel's idea of the last char
158 read is the last char returned by zreadc. */
169 r = lseek (fd, -off, SEEK_CUR);