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-rw-r--r--xlators/features/changelog/lib/src/gf-changelog-helpers.c180
1 files changed, 180 insertions, 0 deletions
diff --git a/xlators/features/changelog/lib/src/gf-changelog-helpers.c b/xlators/features/changelog/lib/src/gf-changelog-helpers.c
new file mode 100644
index 000000000..1eef8bf04
--- /dev/null
+++ b/xlators/features/changelog/lib/src/gf-changelog-helpers.c
@@ -0,0 +1,180 @@
+/*
+ Copyright (c) 2013 Red Hat, Inc. <http://www.redhat.com>
+ This file is part of GlusterFS.
+
+ This file is licensed to you under your choice of the GNU Lesser
+ General Public License, version 3 or any later version (LGPLv3 or
+ later), or the GNU General Public License, version 2 (GPLv2), in all
+ cases as published by the Free Software Foundation.
+*/
+
+#include "changelog-mem-types.h"
+#include "gf-changelog-helpers.h"
+
+ssize_t gf_changelog_read_path (int fd, char *buffer, size_t bufsize)
+{
+ return read (fd, buffer, bufsize);
+}
+
+size_t
+gf_changelog_write (int fd, char *buffer, size_t len)
+{
+ ssize_t size = 0;
+ size_t writen = 0;
+
+ while (writen < len) {
+ size = write (fd,
+ buffer + writen, len - writen);
+ if (size <= 0)
+ break;
+
+ writen += size;
+ }
+
+ return writen;
+}
+
+void
+gf_rfc3986_encode (unsigned char *s, char *enc, char *estr)
+{
+ for (; *s; s++) {
+ if (estr[*s])
+ sprintf(enc, "%c", estr[*s]);
+ else
+ sprintf(enc, "%%%02X", *s);
+ while (*++enc);
+ }
+}
+
+/**
+ * thread safe version of readline with buffering
+ * (taken from Unix Network Programming Volume I, W.R. Stevens)
+ *
+ * This is favoured over fgets() as we'd need to ftruncate()
+ * (see gf_changelog_scan() API) to record new changelog files.
+ * stream open functions does have a truncate like api (although
+ * that can be done via @fflush(fp), @ftruncate(fd) and @fseek(fp),
+ * but this involves mixing POSIX file descriptors and stream FILE *).
+ *
+ * NOTE: This implmentation still does work with more than one fd's
+ * used to perform gf_readline(). For this very reason it's not
+ * made a part of libglusterfs.
+ */
+
+static pthread_key_t rl_key;
+static pthread_once_t rl_once = PTHREAD_ONCE_INIT;
+
+static void
+readline_destructor (void *ptr)
+{
+ GF_FREE (ptr);
+}
+
+static void
+readline_once (void)
+{
+ pthread_key_create (&rl_key, readline_destructor);
+}
+
+static ssize_t
+my_read (read_line_t *tsd, int fd, char *ptr)
+{
+ if (tsd->rl_cnt <= 0) {
+ if ( (tsd->rl_cnt = read (fd, tsd->rl_buf, MAXLINE)) < 0 )
+ return -1;
+ else if (tsd->rl_cnt == 0)
+ return 0;
+ tsd->rl_bufptr = tsd->rl_buf;
+ }
+
+ tsd->rl_cnt--;
+ *ptr = *tsd->rl_bufptr++;
+ return 1;
+}
+
+static int
+gf_readline_init_once (read_line_t **tsd)
+{
+ if (pthread_once (&rl_once, readline_once) != 0)
+ return -1;
+
+ *tsd = pthread_getspecific (rl_key);
+ if (*tsd)
+ goto out;
+
+ *tsd = GF_CALLOC (1, sizeof (**tsd),
+ gf_changelog_mt_libgfchangelog_rl_t);
+ if (!*tsd)
+ return -1;
+
+ if (pthread_setspecific (rl_key, *tsd) != 0)
+ return -1;
+
+ out:
+ return 0;
+}
+
+ssize_t
+gf_readline (int fd, void *vptr, size_t maxlen)
+{
+ size_t n = 0;
+ size_t rc = 0;
+ char c = ' ';
+ char *ptr = NULL;
+ read_line_t *tsd = NULL;
+
+ if (gf_readline_init_once (&tsd))
+ return -1;
+
+ ptr = vptr;
+ for (n = 1; n < maxlen; n++) {
+ if ( (rc = my_read (tsd, fd, &c)) == 1 ) {
+ *ptr++ = c;
+ if (c == '\n')
+ break;
+ } else if (rc == 0) {
+ *ptr = '\0';
+ return (n - 1);
+ } else
+ return -1;
+ }
+
+ *ptr = '\0';
+ return n;
+
+}
+
+off_t
+gf_lseek (int fd, off_t offset, int whence)
+{
+ off_t off = 0;
+ read_line_t *tsd = NULL;
+
+ if (gf_readline_init_once (&tsd))
+ return -1;
+
+ if ( (off = lseek (fd, offset, whence)) == -1)
+ return -1;
+
+ tsd->rl_cnt = 0;
+ tsd->rl_bufptr = tsd->rl_buf;
+
+ return off;
+}
+
+int
+gf_ftruncate (int fd, off_t length)
+{
+ read_line_t *tsd = NULL;
+
+ if (gf_readline_init_once (&tsd))
+ return -1;
+
+ if (ftruncate (fd, 0))
+ return -1;
+
+ tsd->rl_cnt = 0;
+ tsd->rl_bufptr = tsd->rl_buf;
+
+ return 0;
+}