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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 09:51:24 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 09:51:24 +0000
commitf7548d6d28c313cf80e6f3ef89aed16a19815df1 (patch)
treea3f6f2a3f247293bee59ecd28e8cd8ceb6ca064a /src/lib-index/mail-index-util.c
parentInitial commit. (diff)
downloaddovecot-f7548d6d28c313cf80e6f3ef89aed16a19815df1.tar.xz
dovecot-f7548d6d28c313cf80e6f3ef89aed16a19815df1.zip
Adding upstream version 1:2.3.19.1+dfsg1.upstream/1%2.3.19.1+dfsg1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/lib-index/mail-index-util.c')
-rw-r--r--src/lib-index/mail-index-util.c138
1 files changed, 138 insertions, 0 deletions
diff --git a/src/lib-index/mail-index-util.c b/src/lib-index/mail-index-util.c
new file mode 100644
index 0000000..2b27ae1
--- /dev/null
+++ b/src/lib-index/mail-index-util.c
@@ -0,0 +1,138 @@
+/* Copyright (c) 2003-2018 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "array.h"
+#include "bsearch-insert-pos.h"
+#include "mail-index-private.h"
+
+uint32_t mail_index_uint32_to_offset(uint32_t offset)
+{
+ i_assert(offset < 0x40000000);
+ i_assert((offset & 3) == 0);
+
+ offset >>= 2;
+ offset = 0x00000080 | ((offset & 0x0000007f)) |
+ 0x00008000 | ((offset & 0x00003f80) >> 7 << 8) |
+ 0x00800000 | ((offset & 0x001fc000) >> 14 << 16) |
+ 0x80000000 | ((offset & 0x0fe00000) >> 21 << 24);
+
+ return cpu32_to_be(offset);
+}
+
+uint32_t mail_index_offset_to_uint32(uint32_t offset)
+{
+ offset = be32_to_cpu(offset);
+
+ if ((offset & 0x80808080) != 0x80808080)
+ return 0;
+
+ return (((offset & 0x0000007f)) |
+ ((offset & 0x00007f00) >> 8 << 7) |
+ ((offset & 0x007f0000) >> 16 << 14) |
+ ((offset & 0x7f000000) >> 24 << 21)) << 2;
+}
+
+void mail_index_pack_num(uint8_t **p, uint32_t num)
+{
+ /* number continues as long as the highest bit is set */
+ while (num >= 0x80) {
+ **p = (num & 0x7f) | 0x80;
+ *p += 1;
+ num >>= 7;
+ }
+
+ **p = num;
+ *p += 1;
+}
+
+int mail_index_unpack_num(const uint8_t **p, const uint8_t *end,
+ uint32_t *num_r)
+{
+ const uint8_t *c = *p;
+ uint32_t value = 0;
+ unsigned int bits = 0;
+
+ for (;;) {
+ if (unlikely(c == end)) {
+ /* we should never see EOF */
+ *num_r = 0;
+ return -1;
+ }
+
+ value |= (*c & 0x7f) << bits;
+ if (*c < 0x80)
+ break;
+
+ bits += 7;
+ c++;
+ }
+
+ if (unlikely(bits >= 32)) {
+ /* broken input */
+ *p = end;
+ *num_r = 0;
+ return -1;
+ }
+
+ *p = c + 1;
+ *num_r = value;
+ return 0;
+}
+
+static int mail_index_seq_record_cmp(const uint32_t *key_seq,
+ const uint32_t *data_seq)
+{
+ return (int)*key_seq - (int)*data_seq;
+}
+
+bool mail_index_seq_array_lookup(const ARRAY_TYPE(seq_array) *array,
+ uint32_t seq, unsigned int *idx_r)
+{
+ return array_bsearch_insert_pos(array, &seq,
+ mail_index_seq_record_cmp, idx_r);
+}
+
+void mail_index_seq_array_alloc(ARRAY_TYPE(seq_array) *array,
+ size_t record_size)
+{
+ size_t aligned_record_size = (record_size + 3) & ~3U;
+
+ i_assert(!array_is_created(array));
+
+ array_create(array, default_pool,
+ sizeof(uint32_t) + aligned_record_size,
+ 1024 / (sizeof(uint32_t) + aligned_record_size));
+}
+
+bool mail_index_seq_array_add(ARRAY_TYPE(seq_array) *array, uint32_t seq,
+ const void *record, size_t record_size,
+ void *old_record)
+{
+ void *p;
+ unsigned int idx, aligned_record_size;
+
+ /* records need to be 32bit aligned */
+ aligned_record_size = (record_size + 3) & ~3U;
+
+ if (!array_is_created(array))
+ mail_index_seq_array_alloc(array, record_size);
+ i_assert(array->arr.element_size == sizeof(seq) + aligned_record_size);
+
+ if (mail_index_seq_array_lookup(array, seq, &idx)) {
+ /* already there, update */
+ p = array_idx_modifiable(array, idx);
+ if (old_record != NULL) {
+ /* save the old record before overwriting it */
+ memcpy(old_record, PTR_OFFSET(p, sizeof(seq)),
+ record_size);
+ }
+ memcpy(PTR_OFFSET(p, sizeof(seq)), record, record_size);
+ return TRUE;
+ } else {
+ /* insert */
+ p = array_insert_space(array, idx);
+ memcpy(p, &seq, sizeof(seq));
+ memcpy(PTR_OFFSET(p, sizeof(seq)), record, record_size);
+ return FALSE;
+ }
+}