Merge branch 'rs/xdiff-lose-emit-func'

Simplifies the interface between the implementation of "blame" and
underlying xdiff engine, and removes a lot of unused or unnecessary code
from the latter.

By René Scharfe (6) and Ramsay Jones (1)
* rs/xdiff-lose-emit-func:
  builtin/blame.c: Fix a "Using plain integer as NULL pointer" warning
  xdiff: remove unused functions
  xdiff: remove emit_func() and xdi_diff_hunks()
  blame: factor out helper for calling xdi_diff()
  blame: use hunk_func(), part 2
  blame: use hunk_func(), part 1
  xdiff: add hunk_func()

7 files changed, 51 insertions, 119 deletions

diff --git a/builtin/blame.c b/builtin/blame.c
index 324d476ab..24d3dd529 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -88,6 +88,20 @@ struct origin {
 	char path[FLEX_ARRAY];
 };
 
+static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b, long ctxlen,
+		      xdl_emit_hunk_consume_func_t hunk_func, void *cb_data)
+{
+	xpparam_t xpp = {0};
+	xdemitconf_t xecfg = {0};
+	xdemitcb_t ecb = {NULL};
+
+	xpp.flags = xdl_opts;
+	xecfg.ctxlen = ctxlen;
+	xecfg.hunk_func = hunk_func;
+	ecb.priv = cb_data;
+	return xdi_diff(file_a, file_b, &xpp, &xecfg, &ecb);
+}
+
 /*
  * Prepare diff_filespec and convert it using diff textconv API
  * if the textconv driver exists.
@@ -759,12 +773,14 @@ struct blame_chunk_cb_data {
 	long tlno;
 };
 
-static void blame_chunk_cb(void *data, long same, long p_next, long t_next)
+static int blame_chunk_cb(long start_a, long count_a,
+			  long start_b, long count_b, void *data)
 {
 	struct blame_chunk_cb_data *d = data;
-	blame_chunk(d->sb, d->tlno, d->plno, same, d->target, d->parent);
-	d->plno = p_next;
-	d->tlno = t_next;
+	blame_chunk(d->sb, d->tlno, d->plno, start_b, d->target, d->parent);
+	d->plno = start_a + count_a;
+	d->tlno = start_b + count_b;
+	return 0;
 }
 
 /*
@@ -779,8 +795,7 @@ static int pass_blame_to_parent(struct scoreboard *sb,
 	int last_in_target;
 	mmfile_t file_p, file_o;
 	struct blame_chunk_cb_data d;
-	xpparam_t xpp;
-	xdemitconf_t xecfg;
+
 	memset(&d, 0, sizeof(d));
 	d.sb = sb; d.target = target; d.parent = parent;
 	last_in_target = find_last_in_target(sb, target);
@@ -791,11 +806,7 @@ static int pass_blame_to_parent(struct scoreboard *sb,
 	fill_origin_blob(&sb->revs->diffopt, target, &file_o);
 	num_get_patch++;
 
-	memset(&xpp, 0, sizeof(xpp));
-	xpp.flags = xdl_opts;
-	memset(&xecfg, 0, sizeof(xecfg));
-	xecfg.ctxlen = 0;
-	xdi_diff_hunks(&file_p, &file_o, blame_chunk_cb, &d, &xpp, &xecfg);
+	diff_hunks(&file_p, &file_o, 0, blame_chunk_cb, &d);
 	/* The rest (i.e. anything after tlno) are the same as the parent */
 	blame_chunk(sb, d.tlno, d.plno, last_in_target, target, parent);
 
@@ -899,12 +910,15 @@ struct handle_split_cb_data {
 	long tlno;
 };
 
-static void handle_split_cb(void *data, long same, long p_next, long t_next)
+static int handle_split_cb(long start_a, long count_a,
+			   long start_b, long count_b, void *data)
 {
 	struct handle_split_cb_data *d = data;
-	handle_split(d->sb, d->ent, d->tlno, d->plno, same, d->parent, d->split);
-	d->plno = p_next;
-	d->tlno = t_next;
+	handle_split(d->sb, d->ent, d->tlno, d->plno, start_b, d->parent,
+		     d->split);
+	d->plno = start_a + count_a;
+	d->tlno = start_b + count_b;
+	return 0;
 }
 
 /*
@@ -922,8 +936,7 @@ static void find_copy_in_blob(struct scoreboard *sb,
 	int cnt;
 	mmfile_t file_o;
 	struct handle_split_cb_data d;
-	xpparam_t xpp;
-	xdemitconf_t xecfg;
+
 	memset(&d, 0, sizeof(d));
 	d.sb = sb; d.ent = ent; d.parent = parent; d.split = split;
 	/*
@@ -943,12 +956,8 @@ static void find_copy_in_blob(struct scoreboard *sb,
 	 * file_o is a part of final image we are annotating.
 	 * file_p partially may match that image.
 	 */
-	memset(&xpp, 0, sizeof(xpp));
-	xpp.flags = xdl_opts;
-	memset(&xecfg, 0, sizeof(xecfg));
-	xecfg.ctxlen = 1;
 	memset(split, 0, sizeof(struct blame_entry [3]));
-	xdi_diff_hunks(file_p, &file_o, handle_split_cb, &d, &xpp, &xecfg);
+	diff_hunks(file_p, &file_o, 1, handle_split_cb, &d);
 	/* remainder, if any, all match the preimage */
 	handle_split(sb, ent, d.tlno, d.plno, ent->num_lines, parent, split);
 }
diff --git a/xdiff-interface.c b/xdiff-interface.c
index 0e2c16922..ecfa05f61 100644
--- a/xdiff-interface.c
+++ b/xdiff-interface.c
@@ -156,50 +156,6 @@ int xdi_diff_outf(mmfile_t *mf1, mmfile_t *mf2,
 	return ret;
 }
 
-struct xdiff_emit_hunk_state {
-	xdiff_emit_hunk_consume_fn consume;
-	void *consume_callback_data;
-};
-
-static int process_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
-			xdemitconf_t const *xecfg)
-{
-	long s1, s2, same, p_next, t_next;
-	xdchange_t *xch, *xche;
-	struct xdiff_emit_hunk_state *state = ecb->priv;
-	xdiff_emit_hunk_consume_fn fn = state->consume;
-	void *consume_callback_data = state->consume_callback_data;
-
-	for (xch = xscr; xch; xch = xche->next) {
-		xche = xdl_get_hunk(xch, xecfg);
-
-		s1 = XDL_MAX(xch->i1 - xecfg->ctxlen, 0);
-		s2 = XDL_MAX(xch->i2 - xecfg->ctxlen, 0);
-		same = s2 + XDL_MAX(xch->i1 - s1, 0);
-		p_next = xche->i1 + xche->chg1;
-		t_next = xche->i2 + xche->chg2;
-
-		fn(consume_callback_data, same, p_next, t_next);
-	}
-	return 0;
-}
-
-int xdi_diff_hunks(mmfile_t *mf1, mmfile_t *mf2,
-		   xdiff_emit_hunk_consume_fn fn, void *consume_callback_data,
-		   xpparam_t const *xpp, xdemitconf_t *xecfg)
-{
-	struct xdiff_emit_hunk_state state;
-	xdemitcb_t ecb;
-
-	memset(&state, 0, sizeof(state));
-	memset(&ecb, 0, sizeof(ecb));
-	state.consume = fn;
-	state.consume_callback_data = consume_callback_data;
-	xecfg->emit_func = (void (*)())process_diff;
-	ecb.priv = &state;
-	return xdi_diff(mf1, mf2, xpp, xecfg, &ecb);
-}
-
 int read_mmfile(mmfile_t *ptr, const char *filename)
 {
 	struct stat st;
diff --git a/xdiff-interface.h b/xdiff-interface.h
index 49d1116fc..eff7762ee 100644
--- a/xdiff-interface.h
+++ b/xdiff-interface.h
@@ -4,15 +4,11 @@
 #include "xdiff/xdiff.h"
 
 typedef void (*xdiff_emit_consume_fn)(void *, char *, unsigned long);
-typedef void (*xdiff_emit_hunk_consume_fn)(void *, long, long, long);
 
 int xdi_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp, xdemitconf_t const *xecfg, xdemitcb_t *ecb);
 int xdi_diff_outf(mmfile_t *mf1, mmfile_t *mf2,
 		  xdiff_emit_consume_fn fn, void *consume_callback_data,
 		  xpparam_t const *xpp, xdemitconf_t const *xecfg);
-int xdi_diff_hunks(mmfile_t *mf1, mmfile_t *mf2,
-		   xdiff_emit_hunk_consume_fn fn, void *consume_callback_data,
-		   xpparam_t const *xpp, xdemitconf_t *xecfg);
 int parse_hunk_header(char *line, int len,
 		      int *ob, int *on,
 		      int *nb, int *nn);
diff --git a/xdiff/xdiff.h b/xdiff/xdiff.h
index 09215afe6..219a3bbca 100644
--- a/xdiff/xdiff.h
+++ b/xdiff/xdiff.h
@@ -86,13 +86,17 @@ typedef struct s_xdemitcb {
 
 typedef long (*find_func_t)(const char *line, long line_len, char *buffer, long buffer_size, void *priv);
 
+typedef int (*xdl_emit_hunk_consume_func_t)(long start_a, long count_a,
+					    long start_b, long count_b,
+					    void *cb_data);
+
 typedef struct s_xdemitconf {
 	long ctxlen;
 	long interhunkctxlen;
 	unsigned long flags;
 	find_func_t find_func;
 	void *find_func_priv;
-	void (*emit_func)();
+	xdl_emit_hunk_consume_func_t hunk_func;
 } xdemitconf_t;
 
 typedef struct s_bdiffparam {
diff --git a/xdiff/xdiffi.c b/xdiff/xdiffi.c
index bc889e878..1b7012a11 100644
--- a/xdiff/xdiffi.c
+++ b/xdiff/xdiffi.c
@@ -538,13 +538,26 @@ void xdl_free_script(xdchange_t *xscr) {
 	}
 }
 
+static int xdl_call_hunk_func(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
+			      xdemitconf_t const *xecfg)
+{
+	xdchange_t *xch, *xche;
+
+	for (xch = xscr; xch; xch = xche->next) {
+		xche = xdl_get_hunk(xch, xecfg);
+		if (xecfg->hunk_func(xch->i1, xche->i1 + xche->chg1 - xch->i1,
+				     xch->i2, xche->i2 + xche->chg2 - xch->i2,
+				     ecb->priv) < 0)
+			return -1;
+	}
+	return 0;
+}
 
 int xdl_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
 	     xdemitconf_t const *xecfg, xdemitcb_t *ecb) {
 	xdchange_t *xscr;
 	xdfenv_t xe;
-	emit_func_t ef = xecfg->emit_func ?
-		(emit_func_t)xecfg->emit_func : xdl_emit_diff;
+	emit_func_t ef = xecfg->hunk_func ? xdl_call_hunk_func : xdl_emit_diff;
 
 	if (xdl_do_diff(mf1, mf2, xpp, &xe) < 0) {
 
diff --git a/xdiff/xutils.c b/xdiff/xutils.c
index 1b3b471ac..ae6ce0d95 100644
--- a/xdiff/xutils.c
+++ b/xdiff/xutils.c
@@ -122,35 +122,6 @@ void *xdl_cha_alloc(chastore_t *cha) {
 	return data;
 }
 
-
-void *xdl_cha_first(chastore_t *cha) {
-	chanode_t *sncur;
-
-	if (!(cha->sncur = sncur = cha->head))
-		return NULL;
-
-	cha->scurr = 0;
-
-	return (char *) sncur + sizeof(chanode_t) + cha->scurr;
-}
-
-
-void *xdl_cha_next(chastore_t *cha) {
-	chanode_t *sncur;
-
-	if (!(sncur = cha->sncur))
-		return NULL;
-	cha->scurr += cha->isize;
-	if (cha->scurr == sncur->icurr) {
-		if (!(sncur = cha->sncur = sncur->next))
-			return NULL;
-		cha->scurr = 0;
-	}
-
-	return (char *) sncur + sizeof(chanode_t) + cha->scurr;
-}
-
-
 long xdl_guess_lines(mmfile_t *mf, long sample) {
 	long nl = 0, size, tsize = 0;
 	char const *data, *cur, *top;
@@ -430,20 +401,6 @@ int xdl_num_out(char *out, long val) {
 	return str - out;
 }
 
-
-long xdl_atol(char const *str, char const **next) {
-	long val, base;
-	char const *top;
-
-	for (top = str; XDL_ISDIGIT(*top); top++);
-	if (next)
-		*next = top;
-	for (val = 0, base = 1, top--; top >= str; top--, base *= 10)
-		val += base * (long)(*top - '0');
-	return val;
-}
-
-
 int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
 		      const char *func, long funclen, xdemitcb_t *ecb) {
 	int nb = 0;
diff --git a/xdiff/xutils.h b/xdiff/xutils.h
index 714719a89..ad1428ed6 100644
--- a/xdiff/xutils.h
+++ b/xdiff/xutils.h
@@ -31,14 +31,11 @@ int xdl_emit_diffrec(char const *rec, long size, char const *pre, long psize,
 int xdl_cha_init(chastore_t *cha, long isize, long icount);
 void xdl_cha_free(chastore_t *cha);
 void *xdl_cha_alloc(chastore_t *cha);
-void *xdl_cha_first(chastore_t *cha);
-void *xdl_cha_next(chastore_t *cha);
 long xdl_guess_lines(mmfile_t *mf, long sample);
 int xdl_recmatch(const char *l1, long s1, const char *l2, long s2, long flags);
 unsigned long xdl_hash_record(char const **data, char const *top, long flags);
 unsigned int xdl_hashbits(unsigned int size);
 int xdl_num_out(char *out, long val);
-long xdl_atol(char const *str, char const **next);
 int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
 		      const char *func, long funclen, xdemitcb_t *ecb);
 int xdl_fall_back_diff(xdfenv_t *diff_env, xpparam_t const *xpp,