Re: Branch Name Case Sensitivity

From: Lee Hopkins <leerhop@gmail.com>
Date: Mar 1, 2014, 02:42 UTC
Message-ID: <CAJHY66EP539ZsLJcmHcnRQcOqcLqXK-M45wME9DkKkqmumg8fA@mail.gmail.com>
In-Reply-To: <xmqq7g8eu891.fsf@gitster.dls.corp.google.com>

I went ahead and took a stab at a solution. My solution is more aggressive than a warning, I actually prevent the creation of ambiguous refs. My changes are also in refs.c, which may not be appropriate, but it seemed like the natural place.

I have never contributed to Git (in fact this is my first dive into the source) and my C is a bit rusty, so bear with me, this is just a suggestion:

---
 refs.c |   31 ++++++++++++++++++++++++-------
 1 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/refs.c b/refs.c
index 89228e2..12ccdac 100644
--- a/refs.c
+++ b/refs.c
@@ -359,14 +359,24 @@ struct string_slice {
  const char *str;
 };

+static int ref_entry_ncmp(const void *key_, const void *ent_, int
(*cmp_fn)(const char *, const char *, size_t))
+{
+    const struct string_slice *key = key_;
+    const struct ref_entry *ent = *(const struct ref_entry * const *)ent_;
+    int cmp = cmp_fn(key->str, ent->name, key->len);
+    if (cmp)
+        return cmp;
+    return '\0' - (unsigned char)ent->name[key->len];
+}
+
 static int ref_entry_cmp_sslice(const void *key_, const void *ent_)
 {
- const struct string_slice *key = key_;
- const struct ref_entry *ent = *(const struct ref_entry * const *)ent_;
- int cmp = strncmp(key->str, ent->name, key->len);
- if (cmp)
- return cmp;
- return '\0' - (unsigned char)ent->name[key->len];
+ return ref_entry_ncmp(key_, ent_, strncmp);
+}
+
+static int ref_entry_casecmp_sslice(const void *key_, const void *ent_)
+{
+    return ref_entry_ncmp(key_, ent_, strncasecmp);
 }

 /*
@@ -378,6 +388,7 @@ static int search_ref_dir(struct ref_dir *dir,
const char *refname, size_t len)
 {
  struct ref_entry **r;
  struct string_slice key;
+    int (*cmp_fn)(const void *, const void *);

  if (refname == NULL || !dir->nr)
  return -1;
@@ -385,8 +396,14 @@ static int search_ref_dir(struct ref_dir *dir,
const char *refname, size_t len)
  sort_ref_dir(dir);
  key.len = len;
  key.str = refname;
+
+    if(ignore_case)
+        cmp_fn = ref_entry_casecmp_sslice;
+    else
+        cmp_fn = ref_entry_cmp_sslice;
+
  r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries),
-    ref_entry_cmp_sslice);
+    cmp_fn);

  if (r == NULL)
  return -1;
--