Revision f6a1e1e288d13472f5f7fe2b907bb8c0bd69a018 authored by Jim Hill on 18 May 2015, 00:41:45 UTC, committed by Junio C Hamano on 18 May 2015, 17:15:20 UTC
`git add` of an empty file with a filter pops complaints from
`copy_fd` about a bad file descriptor.
This traces back to these lines in sha1_file.c:index_core:
if (!size) {
ret = index_mem(sha1, NULL, size, type, path, flags);
The problem here is that content to be added to the index can be
supplied from an fd, or from a memory buffer, or from a pathname. This
call is supplying a NULL buffer pointer and a zero size.
Downstream logic takes the complete absence of a buffer to mean the
data is to be found elsewhere -- for instance, these, from convert.c:
if (params->src) {
write_err = (write_in_full(child_process.in, params->src, params->size) < 0);
} else {
write_err = copy_fd(params->fd, child_process.in);
}
~If there's a buffer, write from that, otherwise the data must be coming
from an open fd.~
Perfectly reasonable logic in a routine that's going to write from
either a buffer or an fd.
So change `index_core` to supply an empty buffer when indexing an empty
file.
There's a patch out there that instead changes the logic quoted above to
take a `-1` fd to mean "use the buffer", but it seems to me that the
distinction between a missing buffer and an empty one carries intrinsic
semantics, where the logic change is adapting the code to handle
incorrect arguments.
Signed-off-by: Jim Hill <gjthill@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
1 parent 282616c
diffcore.h
/*
* Copyright (C) 2005 Junio C Hamano
*/
#ifndef DIFFCORE_H
#define DIFFCORE_H
/* This header file is internal between diff.c and its diff transformers
* (e.g. diffcore-rename, diffcore-pickaxe). Never include this header
* in anything else.
*/
/* We internally use unsigned short as the score value,
* and rely on an int capable to hold 32-bits. -B can take
* -Bmerge_score/break_score format and the two scores are
* passed around in one int (high 16-bit for merge and low 16-bit
* for break).
*/
#define MAX_SCORE 60000.0
#define DEFAULT_RENAME_SCORE 30000 /* rename/copy similarity minimum (50%) */
#define DEFAULT_BREAK_SCORE 30000 /* minimum for break to happen (50%) */
#define DEFAULT_MERGE_SCORE 36000 /* maximum for break-merge to happen (60%) */
#define MINIMUM_BREAK_SIZE 400 /* do not break a file smaller than this */
struct userdiff_driver;
struct diff_filespec {
unsigned char sha1[20];
char *path;
void *data;
void *cnt_data;
unsigned long size;
int count; /* Reference count */
int rename_used; /* Count of rename users */
unsigned short mode; /* file mode */
unsigned sha1_valid : 1; /* if true, use sha1 and trust mode;
* if false, use the name and read from
* the filesystem.
*/
#define DIFF_FILE_VALID(spec) (((spec)->mode) != 0)
unsigned should_free : 1; /* data should be free()'ed */
unsigned should_munmap : 1; /* data should be munmap()'ed */
unsigned dirty_submodule : 2; /* For submodules: its work tree is dirty */
#define DIRTY_SUBMODULE_UNTRACKED 1
#define DIRTY_SUBMODULE_MODIFIED 2
unsigned is_stdin : 1;
unsigned has_more_entries : 1; /* only appear in combined diff */
/* data should be considered "binary"; -1 means "don't know yet" */
signed int is_binary : 2;
struct userdiff_driver *driver;
};
extern struct diff_filespec *alloc_filespec(const char *);
extern void free_filespec(struct diff_filespec *);
extern void fill_filespec(struct diff_filespec *, const unsigned char *,
int, unsigned short);
extern int diff_populate_filespec(struct diff_filespec *, int);
extern void diff_free_filespec_data(struct diff_filespec *);
extern void diff_free_filespec_blob(struct diff_filespec *);
extern int diff_filespec_is_binary(struct diff_filespec *);
struct diff_filepair {
struct diff_filespec *one;
struct diff_filespec *two;
unsigned short int score;
char status; /* M C R A D U etc. (see Documentation/diff-format.txt or DIFF_STATUS_* in diff.h) */
unsigned broken_pair : 1;
unsigned renamed_pair : 1;
unsigned is_unmerged : 1;
unsigned done_skip_stat_unmatch : 1;
unsigned skip_stat_unmatch_result : 1;
};
#define DIFF_PAIR_UNMERGED(p) ((p)->is_unmerged)
#define DIFF_PAIR_RENAME(p) ((p)->renamed_pair)
#define DIFF_PAIR_BROKEN(p) \
( (!DIFF_FILE_VALID((p)->one) != !DIFF_FILE_VALID((p)->two)) && \
((p)->broken_pair != 0) )
#define DIFF_PAIR_TYPE_CHANGED(p) \
((S_IFMT & (p)->one->mode) != (S_IFMT & (p)->two->mode))
#define DIFF_PAIR_MODE_CHANGED(p) ((p)->one->mode != (p)->two->mode)
extern void diff_free_filepair(struct diff_filepair *);
extern int diff_unmodified_pair(struct diff_filepair *);
struct diff_queue_struct {
struct diff_filepair **queue;
int alloc;
int nr;
};
#define DIFF_QUEUE_CLEAR(q) \
do { \
(q)->queue = NULL; \
(q)->nr = (q)->alloc = 0; \
} while (0)
extern struct diff_queue_struct diff_queued_diff;
extern struct diff_filepair *diff_queue(struct diff_queue_struct *,
struct diff_filespec *,
struct diff_filespec *);
extern void diff_q(struct diff_queue_struct *, struct diff_filepair *);
extern void diffcore_break(int);
extern void diffcore_rename(struct diff_options *);
extern void diffcore_merge_broken(void);
extern void diffcore_pickaxe(struct diff_options *);
extern void diffcore_order(const char *orderfile);
/* low-level interface to diffcore_order */
struct obj_order {
void *obj; /* setup by caller */
/* setup/used by order_objects() */
int orig_order;
int order;
};
typedef const char *(*obj_path_fn_t)(void *obj);
void order_objects(const char *orderfile, obj_path_fn_t obj_path,
struct obj_order *objs, int nr);
#define DIFF_DEBUG 0
#if DIFF_DEBUG
void diff_debug_filespec(struct diff_filespec *, int, const char *);
void diff_debug_filepair(const struct diff_filepair *, int);
void diff_debug_queue(const char *, struct diff_queue_struct *);
#else
#define diff_debug_filespec(a,b,c) do { /* nothing */ } while (0)
#define diff_debug_filepair(a,b) do { /* nothing */ } while (0)
#define diff_debug_queue(a,b) do { /* nothing */ } while (0)
#endif
extern int diffcore_count_changes(struct diff_filespec *src,
struct diff_filespec *dst,
void **src_count_p,
void **dst_count_p,
unsigned long delta_limit,
unsigned long *src_copied,
unsigned long *literal_added);
#endif
Computing file changes ...
