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-rw-r--r--common/xreadline.c127
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diff --git a/common/xreadline.c b/common/xreadline.c
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+/* xreadline.c - fgets replacement function
+ * Copyright (C) 1999, 2004 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of either
+ *
+ * - the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or (at
+ * your option) any later version.
+ *
+ * or
+ *
+ * - the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * or both in parallel, as here.
+ *
+ * This file 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 this program; if not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#include "util.h"
+
+
+/* Same as fgets() but if the provided buffer is too short a larger
+ one will be allocated. This is similar to getline. A line is
+ considered a byte stream ending in a LF.
+
+ If MAX_LENGTH is not NULL, it shall point to a value with the
+ maximum allowed allocation.
+
+ Returns the length of the line. EOF is indicated by a line of
+ length zero. A truncated line is indicated by setting the value at
+ MAX_LENGTH to 0. If the returned value is less then 0 not enough
+ memory was enable and ERRNO is set accordingly.
+
+ If a line has been truncated, the file pointer is moved forward to
+ the end of the line so that the next read starts with the next
+ line. Note that MAX_LENGTH must be re-initialzied in this case.
+
+ Note: The returned buffer is allocated with enough extra space to
+ append a CR,LF,Nul
+ */
+ssize_t
+read_line (FILE *fp,
+ char **addr_of_buffer, size_t *length_of_buffer,
+ size_t *max_length)
+{
+ int c;
+ char *buffer = *addr_of_buffer;
+ size_t length = *length_of_buffer;
+ size_t nbytes = 0;
+ size_t maxlen = max_length? *max_length : 0;
+ char *p;
+
+ if (!buffer)
+ { /* No buffer given - allocate a new one. */
+ length = 256;
+ buffer = xtrymalloc (length);
+ *addr_of_buffer = buffer;
+ if (!buffer)
+ {
+ *length_of_buffer = 0;
+ if (max_length)
+ *max_length = 0;
+ return -1;
+ }
+ *length_of_buffer = length;
+ }
+
+ length -= 3; /* Reserve 3 bytes for CR,LF,EOL. */
+ p = buffer;
+ while ((c = getc (fp)) != EOF)
+ {
+ if (nbytes == length)
+ { /* Enlarge the buffer. */
+ if (maxlen && length > maxlen) /* But not beyond our limit. */
+ {
+ /* Skip the rest of the line. */
+ while (c != '\n' && (c=getc (fp)) != EOF)
+ ;
+ *p++ = '\n'; /* Always append a LF (we reserved some space). */
+ nbytes++;
+ if (max_length)
+ *max_length = 0; /* Indicate truncation. */
+ break; /* the while loop. */
+ }
+ length += 3; /* Adjust for the reserved bytes. */
+ length += length < 1024? 256 : 1024;
+ *addr_of_buffer = xtryrealloc (buffer, length);
+ if (!*addr_of_buffer)
+ {
+ int save_errno = errno;
+ xfree (buffer);
+ *length_of_buffer = 0;
+ if (max_length)
+ *max_length = 0;
+ gpg_err_set_errno (save_errno);
+ return -1;
+ }
+ buffer = *addr_of_buffer;
+ *length_of_buffer = length;
+ length -= 3;
+ p = buffer + nbytes;
+ }
+ *p++ = c;
+ nbytes++;
+ if (c == '\n')
+ break;
+ }
+ *p = 0; /* Make sure the line is a string. */
+
+ return nbytes;
+}