From 86ab7f0ccaed279271d562049c923a6264d2fc70 Mon Sep 17 00:00:00 2001
From: Michael Haggerty <mhagger@alum.mit.edu>
Date: Fri, 12 Aug 2011 23:43:04 +0200
Subject: [PATCH 1/7] Add a file comment
Consolidate here a few general comments plus links to other
documentation. Delete a comment with an out-of-date description of
the .gitattributes file format.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
attr.c | 26 ++++++++++----------------
1 file changed, 10 insertions(+), 16 deletions(-)
diff --git a/attr.c b/attr.c
index f6b3f7e850f..6bc7ae91926 100644
--- a/attr.c
+++ b/attr.c
@@ -1,3 +1,12 @@
+/*
+ * Handle git attributes. See gitattributes(5) for a description of
+ * the file syntax, and Documentation/technical/api-gitattributes.txt
+ * for a description of the API.
+ *
+ * One basic design decision here is that we are not going to support
+ * an insanely large number of attributes.
+ */
+
#define NO_THE_INDEX_COMPATIBILITY_MACROS
#include "cache.h"
#include "exec_cmd.h"
@@ -13,12 +22,7 @@ static const char git_attr__unknown[] = "(builtin)unknown";
static const char *attributes_file;
-/*
- * The basic design decision here is that we are not going to have
- * insanely large number of attributes.
- *
- * This is a randomly chosen prime.
- */
+/* This is a randomly chosen prime. */
#define HASHSIZE 257
#ifndef DEBUG_ATTR
@@ -103,16 +107,6 @@ struct git_attr *git_attr(const char *name)
return git_attr_internal(name, strlen(name));
}
-/*
- * .gitattributes file is one line per record, each of which is
- *
- * (1) glob pattern.
- * (2) whitespace
- * (3) whitespace separated list of attribute names, each of which
- * could be prefixed with '-' to mean "set to false", '!' to mean
- * "unset".
- */
-
/* What does a matched pattern decide? */
struct attr_state {
struct git_attr *attr;
From ba845b755078a043312119609c1ddd7406b20979 Mon Sep 17 00:00:00 2001
From: Michael Haggerty <mhagger@alum.mit.edu>
Date: Fri, 12 Aug 2011 23:43:05 +0200
Subject: [PATCH 2/7] Document struct match_attr
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
attr.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/attr.c b/attr.c
index 6bc7ae91926..c33e4135c3a 100644
--- a/attr.c
+++ b/attr.c
@@ -113,6 +113,20 @@ struct attr_state {
const char *setto;
};
+/*
+ * One rule, as from a .gitattributes file.
+ *
+ * If is_macro is true, then u.attr is a pointer to the git_attr being
+ * defined.
+ *
+ * If is_macro is false, then u.pattern points at the filename pattern
+ * to which the rule applies. (The memory pointed to is part of the
+ * memory block allocated for the match_attr instance.)
+ *
+ * In either case, num_attr is the number of attributes affected by
+ * this rule, and state is an array listing them. The attributes are
+ * listed as they appear in the file (macros unexpanded).
+ */
struct match_attr {
union {
char *pattern;
From 4c7517c9cc7cfc7961a5c31d7539a71f35fae2c2 Mon Sep 17 00:00:00 2001
From: Michael Haggerty <mhagger@alum.mit.edu>
Date: Fri, 12 Aug 2011 23:43:06 +0200
Subject: [PATCH 3/7] Increment num_attr in parse_attr_line(), not parse_attr()
num_attr is incremented iff parse_attr() returns non-NULL. So do the
counting in parse_attr_line() instead of within parse_attr(). This
allows an integer rather than a pointer to an integer to be passed to
parse_attr().
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
attr.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/attr.c b/attr.c
index c33e4135c3a..cac550decd4 100644
--- a/attr.c
+++ b/attr.c
@@ -140,7 +140,7 @@ struct match_attr {
static const char blank[] = " \t\r\n";
static const char *parse_attr(const char *src, int lineno, const char *cp,
- int *num_attr, struct match_attr *res)
+ int num_attr, struct match_attr *res)
{
const char *ep, *equals;
int len;
@@ -167,7 +167,7 @@ static const char *parse_attr(const char *src, int lineno, const char *cp,
} else {
struct attr_state *e;
- e = &(res->state[*num_attr]);
+ e = &(res->state[num_attr]);
if (*cp == '-' || *cp == '!') {
e->setto = (*cp == '-') ? ATTR__FALSE : ATTR__UNSET;
cp++;
@@ -180,7 +180,6 @@ static const char *parse_attr(const char *src, int lineno, const char *cp,
}
e->attr = git_attr_internal(cp, len);
}
- (*num_attr)++;
return ep + strspn(ep, blank);
}
@@ -226,9 +225,10 @@ static struct match_attr *parse_attr_line(const char *line, const char *src,
cp = name + namelen;
cp = cp + strspn(cp, blank);
while (*cp) {
- cp = parse_attr(src, lineno, cp, &num_attr, res);
+ cp = parse_attr(src, lineno, cp, num_attr, res);
if (!cp)
return NULL;
+ num_attr++;
}
if (pass)
break;
From d175129857fe712bc7a4d882b0b9ef9f9d0a337e Mon Sep 17 00:00:00 2001
From: Michael Haggerty <mhagger@alum.mit.edu>
Date: Fri, 12 Aug 2011 23:43:07 +0200
Subject: [PATCH 4/7] Change parse_attr() to take a pointer to struct
attr_state
parse_attr() only needs access to the attr_state to which it should
store its results, not to the whole match_attr structure. This change
also removes the need for it to know num_attr. Change its signature
accordingly and add a comment.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
attr.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)
diff --git a/attr.c b/attr.c
index cac550decd4..f23f62a6b13 100644
--- a/attr.c
+++ b/attr.c
@@ -139,8 +139,15 @@ struct match_attr {
static const char blank[] = " \t\r\n";
+/*
+ * Parse a whitespace-delimited attribute state (i.e., "attr",
+ * "-attr", "!attr", or "attr=value") from the string starting at src.
+ * If e is not NULL, write the results to *e. Return a pointer to the
+ * remainder of the string (with leading whitespace removed), or NULL
+ * if there was an error.
+ */
static const char *parse_attr(const char *src, int lineno, const char *cp,
- int num_attr, struct match_attr *res)
+ struct attr_state *e)
{
const char *ep, *equals;
int len;
@@ -153,7 +160,7 @@ static const char *parse_attr(const char *src, int lineno, const char *cp,
len = equals - cp;
else
len = ep - cp;
- if (!res) {
+ if (!e) {
if (*cp == '-' || *cp == '!') {
cp++;
len--;
@@ -165,9 +172,6 @@ static const char *parse_attr(const char *src, int lineno, const char *cp,
return NULL;
}
} else {
- struct attr_state *e;
-
- e = &(res->state[num_attr]);
if (*cp == '-' || *cp == '!') {
e->setto = (*cp == '-') ? ATTR__FALSE : ATTR__UNSET;
cp++;
@@ -225,7 +229,8 @@ static struct match_attr *parse_attr_line(const char *line, const char *src,
cp = name + namelen;
cp = cp + strspn(cp, blank);
while (*cp) {
- cp = parse_attr(src, lineno, cp, num_attr, res);
+ cp = parse_attr(src, lineno, cp,
+ pass ? &(res->state[num_attr]) : NULL);
if (!cp)
return NULL;
num_attr++;
From 85c4a0d0482525480de4b575445ef8721858eff7 Mon Sep 17 00:00:00 2001
From: Michael Haggerty <mhagger@alum.mit.edu>
Date: Fri, 12 Aug 2011 23:43:08 +0200
Subject: [PATCH 5/7] Determine the start of the states outside of the pass
loop
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
attr.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/attr.c b/attr.c
index f23f62a6b13..a7d1aa95d21 100644
--- a/attr.c
+++ b/attr.c
@@ -192,7 +192,7 @@ static struct match_attr *parse_attr_line(const char *line, const char *src,
{
int namelen;
int num_attr;
- const char *cp, *name;
+ const char *cp, *name, *states;
struct match_attr *res = NULL;
int pass;
int is_macro;
@@ -223,11 +223,13 @@ static struct match_attr *parse_attr_line(const char *line, const char *src,
else
is_macro = 0;
+ states = name + namelen;
+ states += strspn(states, blank);
+
for (pass = 0; pass < 2; pass++) {
/* pass 0 counts and allocates, pass 1 fills */
num_attr = 0;
- cp = name + namelen;
- cp = cp + strspn(cp, blank);
+ cp = states;
while (*cp) {
cp = parse_attr(src, lineno, cp,
pass ? &(res->state[num_attr]) : NULL);
From e0a5f9aaae4eea67f513e382d9d917388313d2a6 Mon Sep 17 00:00:00 2001
From: Michael Haggerty <mhagger@alum.mit.edu>
Date: Fri, 12 Aug 2011 23:43:09 +0200
Subject: [PATCH 6/7] Change while loop into for loop
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
attr.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/attr.c b/attr.c
index a7d1aa95d21..b56542e7234 100644
--- a/attr.c
+++ b/attr.c
@@ -228,14 +228,11 @@ static struct match_attr *parse_attr_line(const char *line, const char *src,
for (pass = 0; pass < 2; pass++) {
/* pass 0 counts and allocates, pass 1 fills */
- num_attr = 0;
- cp = states;
- while (*cp) {
+ for (cp = states, num_attr = 0; *cp; num_attr++) {
cp = parse_attr(src, lineno, cp,
pass ? &(res->state[num_attr]) : NULL);
if (!cp)
return NULL;
- num_attr++;
}
if (pass)
break;
From d68e1c183c056ae583a45b610d086ac078886154 Mon Sep 17 00:00:00 2001
From: Michael Haggerty <mhagger@alum.mit.edu>
Date: Fri, 12 Aug 2011 23:43:10 +0200
Subject: [PATCH 7/7] Unroll the loop over passes
The passes no longer share much code, and the unrolled code is easier
to understand.
Use a new index variable instead of num_attr for the second loop, as
we are no longer counting attributes but rather indexing through them.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
attr.c | 51 ++++++++++++++++++++++++++-------------------------
1 file changed, 26 insertions(+), 25 deletions(-)
diff --git a/attr.c b/attr.c
index b56542e7234..6abaaece326 100644
--- a/attr.c
+++ b/attr.c
@@ -191,10 +191,9 @@ static struct match_attr *parse_attr_line(const char *line, const char *src,
int lineno, int macro_ok)
{
int namelen;
- int num_attr;
+ int num_attr, i;
const char *cp, *name, *states;
struct match_attr *res = NULL;
- int pass;
int is_macro;
cp = line + strspn(line, blank);
@@ -226,30 +225,32 @@ static struct match_attr *parse_attr_line(const char *line, const char *src,
states = name + namelen;
states += strspn(states, blank);
- for (pass = 0; pass < 2; pass++) {
- /* pass 0 counts and allocates, pass 1 fills */
- for (cp = states, num_attr = 0; *cp; num_attr++) {
- cp = parse_attr(src, lineno, cp,
- pass ? &(res->state[num_attr]) : NULL);
- if (!cp)
- return NULL;
- }
- if (pass)
- break;
- res = xcalloc(1,
- sizeof(*res) +
- sizeof(struct attr_state) * num_attr +
- (is_macro ? 0 : namelen + 1));
- if (is_macro)
- res->u.attr = git_attr_internal(name, namelen);
- else {
- res->u.pattern = (char *)&(res->state[num_attr]);
- memcpy(res->u.pattern, name, namelen);
- res->u.pattern[namelen] = 0;
- }
- res->is_macro = is_macro;
- res->num_attr = num_attr;
+ /* First pass to count the attr_states */
+ for (cp = states, num_attr = 0; *cp; num_attr++) {
+ cp = parse_attr(src, lineno, cp, NULL);
+ if (!cp)
+ return NULL;
}
+
+ res = xcalloc(1,
+ sizeof(*res) +
+ sizeof(struct attr_state) * num_attr +
+ (is_macro ? 0 : namelen + 1));
+ if (is_macro)
+ res->u.attr = git_attr_internal(name, namelen);
+ else {
+ res->u.pattern = (char *)&(res->state[num_attr]);
+ memcpy(res->u.pattern, name, namelen);
+ res->u.pattern[namelen] = 0;
+ }
+ res->is_macro = is_macro;
+ res->num_attr = num_attr;
+
+ /* Second pass to fill the attr_states */
+ for (cp = states, i = 0; *cp; i++) {
+ cp = parse_attr(src, lineno, cp, &(res->state[i]));
+ }
+
return res;
}