Re: [PATCH 05/38] pack v4: add commit object parsing

On Thu, 5 Sep 2013, SZEDER Gábor wrote:

Hi,


On Thu, Sep 05, 2013 at 02:19:28AM -0400, Nicolas Pitre wrote:

quoted

Let's create another dictionary table to hold the author and committer
entries.  We use the same table format used for tree entries where the
16 bit data prefix is conveniently used to store the timezone value.

In order to copy straight from a commit object buffer, dict_add_entry()
is modified to get the string length as the provided string pointer is
not always be null terminated.

Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
---
 packv4-create.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 89 insertions(+), 9 deletions(-)

diff --git a/packv4-create.c b/packv4-create.c
index eccd9fc..5c08871 100644
--- a/packv4-create.c
+++ b/packv4-create.c

@@ -1,5 +1,5 @@
 /*
- * packv4-create.c: management of dictionary tables used in pack v4
+ * packv4-create.c: creation of dictionary tables and objects used in pack v4
  *
  * (C) Nicolas Pitre <nico@fluxnic.net>
  *

@@ -80,9 +80,9 @@ static void rehash_entries(struct dict_table *t)
 	}
 }
 
-int dict_add_entry(struct dict_table *t, int val, const char *str)
+int dict_add_entry(struct dict_table *t, int val, const char *str, int str_len)
 {
-	int i, val_len = 2, str_len = strlen(str) + 1;
+	int i, val_len = 2;
 
 	if (t->ptr + val_len + str_len > t->size) {

We need a +1 here on the left side, i.e.

        if (t->ptr + val_len + str_len + 1 > t->size) {

Absolutely, good catch.

Sidenote: couldn't we call the 'ptr' field something else, like
end_offset or end_idx?  It took me some headscratching to figure out
why is it OK to compare a pointer to an integer above, or use a
pointer without dereferencing as an index into an array below (because
ptr is, well, not a pointer after all).

Indeed.  This is a remnant of an earlier implementation which didn't use 
realloc() and therefore this used to be a real pointer.

Both issues now addressed in my tree.

Thanks


Nicolas