https://github.com/git/git
Revision a36df79a37c7c643177905ce725dca8e9bd092d3 authored by Jeff King on 09 August 2021, 22:48:39 UTC, committed by Johannes Schindelin on 12 March 2023, 19:31:55 UTC
When parsing our buffer of output from git-log, we have a
find_end_of_line() helper that finds the next newline, and gives us the
number of bytes to move past it, or the size of the whole remaining
buffer if there is no newline.
But trying to handle both those cases leads to some oddities:
- we try to overwrite the newline with NUL in the caller, by writing
over line[len-1]. This is at best redundant, since the helper will
already have done so if it saw a newline. But if it didn't see a
newline, it's actively wrong; we'll overwrite the byte at the end of
the (unterminated) line.
We could solve this just dropping the extra NUL assignment in the
caller and just letting the helper do the right thing. But...
- if we see a "diff --git" line, we'll restore the newline on top of
the NUL byte, so we can pass the string to parse_git_diff_header().
But if there was no newline in the first place, we can't do this.
There's no place to put it (the current code writes a newline
over whatever byte we obliterated earlier). The best we can do is
feed the complete remainder of the buffer to the function (which is,
in fact, a string, by virtue of being a strbuf).
To solve this, the caller needs to know whether we actually found a
newline or not. We could modify find_end_of_line() to return that
information, but we can further observe that it has only one caller.
So let's just inline it in that caller.
Nobody seems to have noticed this case, probably because git-log would
never produce input that doesn't end with a newline. Arguably we could
just return an error as soon as we see that the output does not end in a
newline. But the code to do so actually ends up _longer_, mostly because
of the cleanup we have to do in handling the error.
Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
1 parent 18bc8eb
Tip revision: a36df79a37c7c643177905ce725dca8e9bd092d3 authored by Jeff King on 09 August 2021, 22:48:39 UTC
range-diff: handle unterminated lines in read_patches()
range-diff: handle unterminated lines in read_patches()
Tip revision: a36df79
packfile.h
#ifndef PACKFILE_H
#define PACKFILE_H
#include "cache.h"
#include "oidset.h"
/* in object-store.h */
struct packed_git;
struct object_info;
/*
* Generate the filename to be used for a pack file with checksum "sha1" and
* extension "ext". The result is written into the strbuf "buf", overwriting
* any existing contents. A pointer to buf->buf is returned as a convenience.
*
* Example: odb_pack_name(out, sha1, "idx") => ".git/objects/pack/pack-1234..idx"
*/
char *odb_pack_name(struct strbuf *buf, const unsigned char *sha1, const char *ext);
/*
* Return the name of the (local) packfile with the specified sha1 in
* its name. The return value is a pointer to memory that is
* overwritten each time this function is called.
*/
char *sha1_pack_name(const unsigned char *sha1);
/*
* Return the name of the (local) pack index file with the specified
* sha1 in its name. The return value is a pointer to memory that is
* overwritten each time this function is called.
*/
char *sha1_pack_index_name(const unsigned char *sha1);
/*
* Return the basename of the packfile, omitting any containing directory
* (e.g., "pack-1234abcd[...].pack").
*/
const char *pack_basename(struct packed_git *p);
struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path);
typedef void each_file_in_pack_dir_fn(const char *full_path, size_t full_path_len,
const char *file_pach, void *data);
void for_each_file_in_pack_dir(const char *objdir,
each_file_in_pack_dir_fn fn,
void *data);
/* A hook to report invalid files in pack directory */
#define PACKDIR_FILE_PACK 1
#define PACKDIR_FILE_IDX 2
#define PACKDIR_FILE_GARBAGE 4
extern void (*report_garbage)(unsigned seen_bits, const char *path);
void reprepare_packed_git(struct repository *r);
void install_packed_git(struct repository *r, struct packed_git *pack);
struct packed_git *get_packed_git(struct repository *r);
struct list_head *get_packed_git_mru(struct repository *r);
struct multi_pack_index *get_multi_pack_index(struct repository *r);
struct multi_pack_index *get_local_multi_pack_index(struct repository *r);
struct packed_git *get_all_packs(struct repository *r);
/*
* Give a rough count of objects in the repository. This sacrifices accuracy
* for speed.
*/
unsigned long repo_approximate_object_count(struct repository *r);
#define approximate_object_count() repo_approximate_object_count(the_repository)
struct packed_git *find_sha1_pack(const unsigned char *sha1,
struct packed_git *packs);
void pack_report(void);
/*
* mmap the index file for the specified packfile (if it is not
* already mmapped). Return 0 on success.
*/
int open_pack_index(struct packed_git *);
/*
* munmap the index file for the specified packfile (if it is
* currently mmapped).
*/
void close_pack_index(struct packed_git *);
int close_pack_fd(struct packed_git *p);
uint32_t get_pack_fanout(struct packed_git *p, uint32_t value);
unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
void close_pack_windows(struct packed_git *);
void close_pack(struct packed_git *);
void close_object_store(struct raw_object_store *o);
void unuse_pack(struct pack_window **);
void clear_delta_base_cache(void);
struct packed_git *add_packed_git(const char *path, size_t path_len, int local);
/*
* Unlink the .pack and associated extension files.
* Does not unlink if 'force_delete' is false and the pack-file is
* marked as ".keep".
*/
void unlink_pack_path(const char *pack_name, int force_delete);
/*
* Make sure that a pointer access into an mmap'd index file is within bounds,
* and can provide at least 8 bytes of data.
*
* Note that this is only necessary for variable-length segments of the file
* (like the 64-bit extended offset table), as we compare the size to the
* fixed-length parts when we open the file.
*/
void check_pack_index_ptr(const struct packed_git *p, const void *ptr);
/*
* Perform binary search on a pack-index for a given oid. Packfile is expected to
* have a valid pack-index.
*
* See 'bsearch_hash' for more information.
*/
int bsearch_pack(const struct object_id *oid, const struct packed_git *p, uint32_t *result);
/*
* Write the oid of the nth object within the specified packfile into the first
* parameter. Open the index if it is not already open. Returns 0 on success,
* negative otherwise.
*/
int nth_packed_object_id(struct object_id *, struct packed_git *, uint32_t n);
/*
* Return the offset of the nth object within the specified packfile.
* The index must already be opened.
*/
off_t nth_packed_object_offset(const struct packed_git *, uint32_t n);
/*
* If the object named sha1 is present in the specified packfile,
* return its offset within the packfile; otherwise, return 0.
*/
off_t find_pack_entry_one(const unsigned char *sha1, struct packed_git *);
int is_pack_valid(struct packed_git *);
void *unpack_entry(struct repository *r, struct packed_git *, off_t, enum object_type *, unsigned long *);
unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
int unpack_object_header(struct packed_git *, struct pack_window **, off_t *, unsigned long *);
off_t get_delta_base(struct packed_git *p, struct pack_window **w_curs,
off_t *curpos, enum object_type type,
off_t delta_obj_offset);
void release_pack_memory(size_t);
/* global flag to enable extra checks when accessing packed objects */
extern int do_check_packed_object_crc;
int packed_object_info(struct repository *r,
struct packed_git *pack,
off_t offset, struct object_info *);
void mark_bad_packed_object(struct packed_git *p, const unsigned char *sha1);
const struct packed_git *has_packed_and_bad(struct repository *r, const unsigned char *sha1);
/*
* Iff a pack file in the given repository contains the object named by sha1,
* return true and store its location to e.
*/
int find_pack_entry(struct repository *r, const struct object_id *oid, struct pack_entry *e);
int has_object_pack(const struct object_id *oid);
int has_pack_index(const unsigned char *sha1);
/*
* Return 1 if an object in a promisor packfile is or refers to the given
* object, 0 otherwise.
*/
int is_promisor_object(const struct object_id *oid);
/*
* Expose a function for fuzz testing.
*
* load_idx() parses a block of memory as a packfile index and puts the results
* into a struct packed_git.
*
* This function should not be used directly. It is exposed here only so that we
* have a convenient entry-point for fuzz testing. For real uses, you should
* probably use open_pack_index() or parse_pack_index() instead.
*/
int load_idx(const char *path, const unsigned int hashsz, void *idx_map,
size_t idx_size, struct packed_git *p);
#endif
Computing file changes ...
