mercurial/thirdparty/xdiff/xdiff.h

convert: don't drop commits that are empty in the source when using --filemap

I ran into this when using `hg lfconvert --to-normal` (which uses the filemap
class internally), and saw that commits with nothing but a branch change were
dropped.  We could put in an option that only lfconvert uses internally.  But
silently dropping anything other than a commit where all changes were excluded
seems unintended.  For example, there's a message in mercurial_sink.putcommit()
if it drops an empty commit.  (And the reason that isn't kicking in here is
because lfconvert isn't passing --filemap, so the self.filemapmode conditional
there is always False.)

The naive change of `return not files` broke test-convert-filemap.t, so this is
a little more elaborate than needed for converting from largefiles.

/*
 *  LibXDiff by Davide Libenzi ( File Differential Library )
 *  Copyright (C) 2003  Davide Libenzi
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, see
 *  <http://www.gnu.org/licenses/>.
 *
 *  Davide Libenzi <[e-mail]>
 *
 */

#if !defined(XDIFF_H)
#define XDIFF_H

#ifdef __cplusplus
extern "C" {
#endif /* #ifdef __cplusplus */

#include <stddef.h> /* size_t */

#if !defined(_MSC_VER) || _MSC_VER >= 1600
#include <stdint.h>
#else
/* prior to Visual Studio 2010 */
typedef long long int64_t;
typedef unsigned long long uint64_t;
#endif

/* xpparm_t.flags */
#define XDF_NEED_MINIMAL (1 << 0)

#define XDF_INDENT_HEURISTIC (1 << 23)

/* emit bdiff-style "matched" (a1, a2, b1, b2) hunks instead of "different"
 * (a1, a2 - a1, b1, b2 - b1) hunks */
#define XDL_EMIT_BDIFFHUNK (1 << 4)

typedef struct s_mmfile {
	char *ptr;
	int64_t size;
} mmfile_t;

typedef struct s_mmbuffer {
	char *ptr;
	int64_t size;
} mmbuffer_t;

typedef struct s_xpparam {
	uint64_t flags;
} xpparam_t;

typedef struct s_xdemitcb {
	void *priv;
} xdemitcb_t;

typedef int (*xdl_emit_hunk_consume_func_t)(int64_t start_a, int64_t count_a,
					    int64_t start_b, int64_t count_b,
					    void *cb_data);

typedef struct s_xdemitconf {
	uint64_t flags;
	xdl_emit_hunk_consume_func_t hunk_func;
} xdemitconf_t;


#define xdl_malloc(x) malloc(x)
#define xdl_free(ptr) free(ptr)
#define xdl_realloc(ptr,x) realloc(ptr,x)

void *xdl_mmfile_first(mmfile_t *mmf, int64_t *size);
int64_t xdl_mmfile_size(mmfile_t *mmf);

int xdl_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
	     xdemitconf_t const *xecfg, xdemitcb_t *ecb);

#ifdef __cplusplus
}
#endif /* #ifdef __cplusplus */

#endif /* #if !defined(XDIFF_H) */