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-rw-r--r--lib/sh/zgetline.c126
1 files changed, 126 insertions, 0 deletions
diff --git a/lib/sh/zgetline.c b/lib/sh/zgetline.c
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--- /dev/null
+++ b/lib/sh/zgetline.c
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+/* zgetline - read a line of input from a specified file descriptor and return
+ a pointer to a newly-allocated buffer containing the data. */
+
+/* Copyright (C) 2008-2020 Free Software Foundation, Inc.
+
+ This file is part of GNU Bash, the Bourne Again SHell.
+
+ Bash 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.
+
+ Bash 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 Bash. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <config.h>
+
+#include <sys/types.h>
+
+#if defined (HAVE_UNISTD_H)
+# include <unistd.h>
+#endif
+
+#include <errno.h>
+#include "xmalloc.h"
+
+#if !defined (errno)
+extern int errno;
+#endif
+
+extern ssize_t zread PARAMS((int, char *, size_t));
+extern ssize_t zreadc PARAMS((int, char *));
+extern ssize_t zreadintr PARAMS((int, char *, size_t));
+extern ssize_t zreadcintr PARAMS((int, char *));
+
+typedef ssize_t breadfunc_t PARAMS((int, char *, size_t));
+typedef ssize_t creadfunc_t PARAMS((int, char *));
+
+/* Initial memory allocation for automatic growing buffer in zreadlinec */
+#define GET_LINE_INITIAL_ALLOCATION 16
+
+/* Derived from GNU libc's getline.
+ The behavior is almost the same as getline. See man getline.
+ The differences are
+ (1) using file descriptor instead of FILE *;
+ (2) the order of arguments: the file descriptor comes first;
+ (3) the addition of a fourth argument, DELIM; sets the delimiter to
+ be something other than newline if desired. If setting DELIM,
+ the next argument should be 1; and
+ (4) the addition of a fifth argument, UNBUFFERED_READ; this argument
+ controls whether get_line uses buffering or not to get a byte data
+ from FD. get_line uses zreadc if UNBUFFERED_READ is zero; and
+ uses zread if UNBUFFERED_READ is non-zero.
+
+ Returns number of bytes read or -1 on error. */
+
+ssize_t
+zgetline (fd, lineptr, n, delim, unbuffered_read)
+ int fd;
+ char **lineptr;
+ size_t *n;
+ int delim;
+ int unbuffered_read;
+{
+ int retval;
+ size_t nr;
+ char *line, c;
+
+ if (lineptr == 0 || n == 0 || (*lineptr == 0 && *n != 0))
+ return -1;
+
+ nr = 0;
+ line = *lineptr;
+
+ while (1)
+ {
+ retval = unbuffered_read ? zread (fd, &c, 1) : zreadc(fd, &c);
+
+ if (retval <= 0)
+ {
+ if (line && nr > 0)
+ line[nr] = '\0';
+ break;
+ }
+
+ if (nr + 2 >= *n)
+ {
+ size_t new_size;
+
+ new_size = (*n == 0) ? GET_LINE_INITIAL_ALLOCATION : *n * 2;
+ line = (*n >= new_size) ? NULL : xrealloc (*lineptr, new_size);
+
+ if (line)
+ {
+ *lineptr = line;
+ *n = new_size;
+ }
+ else
+ {
+ if (*n > 0)
+ {
+ (*lineptr)[*n - 1] = '\0';
+ nr = *n - 2;
+ }
+ break;
+ }
+ }
+
+ line[nr] = c;
+ nr++;
+
+ if (c == delim)
+ {
+ line[nr] = '\0';
+ break;
+ }
+ }
+
+ return nr - 1;
+}