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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-09 13:34:27 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-09 13:34:27 +0000
commit4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f (patch)
tree47c1d492e9c956c1cd2b74dbd3b9d8b0db44dc4e /pack.h
parentInitial commit. (diff)
downloadgit-4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f.tar.xz
git-4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f.zip
Adding upstream version 1:2.43.0.upstream/1%2.43.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'pack.h')
-rw-r--r--pack.h129
1 files changed, 129 insertions, 0 deletions
diff --git a/pack.h b/pack.h
new file mode 100644
index 0000000..3ab9e3f
--- /dev/null
+++ b/pack.h
@@ -0,0 +1,129 @@
+#ifndef PACK_H
+#define PACK_H
+
+#include "object.h"
+#include "csum-file.h"
+
+struct packed_git;
+struct pack_window;
+struct repository;
+
+/*
+ * Packed object header
+ */
+#define PACK_SIGNATURE 0x5041434b /* "PACK" */
+#define PACK_VERSION 2
+#define pack_version_ok(v) ((v) == htonl(2) || (v) == htonl(3))
+struct pack_header {
+ uint32_t hdr_signature;
+ uint32_t hdr_version;
+ uint32_t hdr_entries;
+};
+
+/*
+ * The first four bytes of index formats later than version 1 should
+ * start with this signature, as all older git binaries would find this
+ * value illegal and abort reading the file.
+ *
+ * This is the case because the number of objects in a packfile
+ * cannot exceed 1,431,660,000 as every object would need at least
+ * 3 bytes of data and the overall packfile cannot exceed 4 GiB with
+ * version 1 of the index file due to the offsets limited to 32 bits.
+ * Clearly the signature exceeds this maximum.
+ *
+ * Very old git binaries will also compare the first 4 bytes to the
+ * next 4 bytes in the index and abort with a "non-monotonic index"
+ * error if the second 4 byte word is smaller than the first 4
+ * byte word. This would be true in the proposed future index
+ * format as idx_signature would be greater than idx_version.
+ */
+#define PACK_IDX_SIGNATURE 0xff744f63 /* "\377tOc" */
+
+struct pack_idx_option {
+ unsigned flags;
+ /* flag bits */
+#define WRITE_IDX_VERIFY 01 /* verify only, do not write the idx file */
+#define WRITE_IDX_STRICT 02
+#define WRITE_REV 04
+#define WRITE_REV_VERIFY 010
+#define WRITE_MTIMES 020
+
+ uint32_t version;
+ uint32_t off32_limit;
+
+ /*
+ * List of offsets that would fit within off32_limit but
+ * need to be written out as 64-bit entity for byte-for-byte
+ * verification.
+ */
+ int anomaly_alloc, anomaly_nr;
+ uint32_t *anomaly;
+};
+
+void reset_pack_idx_option(struct pack_idx_option *);
+
+/*
+ * Packed object index header
+ */
+struct pack_idx_header {
+ uint32_t idx_signature;
+ uint32_t idx_version;
+};
+
+/*
+ * Common part of object structure used for write_idx_file
+ */
+struct pack_idx_entry {
+ struct object_id oid;
+ uint32_t crc32;
+ off_t offset;
+};
+
+
+struct progress;
+/* Note, the data argument could be NULL if object type is blob */
+typedef int (*verify_fn)(const struct object_id *, enum object_type, unsigned long, void*, int*);
+
+const char *write_idx_file(const char *index_name, struct pack_idx_entry **objects, int nr_objects, const struct pack_idx_option *, const unsigned char *sha1);
+int check_pack_crc(struct packed_git *p, struct pack_window **w_curs, off_t offset, off_t len, unsigned int nr);
+int verify_pack_index(struct packed_git *);
+int verify_pack(struct repository *, struct packed_git *, verify_fn fn, struct progress *, uint32_t);
+off_t write_pack_header(struct hashfile *f, uint32_t);
+void fixup_pack_header_footer(int, unsigned char *, const char *, uint32_t, unsigned char *, off_t);
+char *index_pack_lockfile(int fd, int *is_well_formed);
+
+struct ref;
+
+void write_promisor_file(const char *promisor_name, struct ref **sought, int nr_sought);
+
+const char *write_rev_file(const char *rev_name, struct pack_idx_entry **objects, uint32_t nr_objects, const unsigned char *hash, unsigned flags);
+const char *write_rev_file_order(const char *rev_name, uint32_t *pack_order, uint32_t nr_objects, const unsigned char *hash, unsigned flags);
+
+/*
+ * The "hdr" output buffer should be at least this big, which will handle sizes
+ * up to 2^67.
+ */
+#define MAX_PACK_OBJECT_HEADER 10
+int encode_in_pack_object_header(unsigned char *hdr, int hdr_len,
+ enum object_type, uintmax_t);
+
+#define PH_ERROR_EOF (-1)
+#define PH_ERROR_PACK_SIGNATURE (-2)
+#define PH_ERROR_PROTOCOL (-3)
+int read_pack_header(int fd, struct pack_header *);
+
+struct packing_data;
+
+struct hashfile *create_tmp_packfile(char **pack_tmp_name);
+void stage_tmp_packfiles(struct strbuf *name_buffer,
+ const char *pack_tmp_name,
+ struct pack_idx_entry **written_list,
+ uint32_t nr_written,
+ struct packing_data *to_pack,
+ struct pack_idx_option *pack_idx_opts,
+ unsigned char hash[],
+ char **idx_tmp_name);
+void rename_tmp_packfile_idx(struct strbuf *basename,
+ char **idx_tmp_name);
+
+#endif