From b7a3aeaccd84cd79898da3fc04463e8126911b19 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <icculus@icculus.org>
Date: Wed, 12 Oct 2005 22:03:28 +0000
Subject: [PATCH] Fixed version of locateInStringList() from Matze Braun.

---
 CHANGELOG |  1 +
 CREDITS   |  3 ++-
 physfs.c  | 40 +++++++++++++++-------------------------
 3 files changed, 18 insertions(+), 26 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG
index 74b230bf..b2fe8fa0 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -2,6 +2,7 @@
  * CHANGELOG.
  */
 
+10122005 - Fixed locateInStringList() in physfs.c (thanks, Matze!).
 09192005 - Make unix mutexes recursive above pthread layer...fixes deadlock on
            MacOS X, for now.
 09182005 - API BREAKAGE: PHYSFS_enumerateFilesCallback() now passes the
diff --git a/CREDITS b/CREDITS
index 81931fd9..cdef5129 100644
--- a/CREDITS
+++ b/CREDITS
@@ -84,7 +84,8 @@ MacOS Classic fixes,
 MPW support:
     Chris Taylor
 
-Mingw support:
+Mingw support,
+General bug fixes:
     Matze Braun
 
 Bug fixes:
diff --git a/physfs.c b/physfs.c
index 7cfcca9c..05da6201 100644
--- a/physfs.c
+++ b/physfs.c
@@ -1459,37 +1459,30 @@ static int locateInStringList(const char *str,
                               char **list,
                               PHYSFS_uint32 *pos)
 {
-    PHYSFS_uint32 hi = *pos - 1;
+    PHYSFS_uint32 len = *pos;
+    PHYSFS_uint32 half_len;
     PHYSFS_uint32 lo = 0;
-    PHYSFS_uint32 i = hi >> 1;
+    PHYSFS_uint32 middle;
     int cmp;
 
-    assert(*pos != 0);  /* this doesn't work with empty lists! */
-
-    while (hi != lo)
+    while (len > 0)
     {
-        cmp = strcmp(list[i], str);
+        half_len = len >> 1;
+        middle = lo + half_len;
+        cmp = strcmp(list[middle], str);
+
         if (cmp == 0)  /* it's in the list already. */
             return(1);
-        else if (cmp < 0)
-        {
-            hi = i;
-            i = lo + ((hi - lo) >> 1);
-        } /* else if */
+        else if (cmp > 0)
+            len = half_len;
         else
         {
-            lo = i + 1;
-            i = lo + ((1 + hi - lo) >> 1);
+            lo = middle + 1;
+            len -= half_len + 1;
         } /* else */
     } /* while */
 
-    /* hi == lo, check it in case it's the match... */
-    cmp = strcmp(list[lo], str);
-    if (cmp == 0)
-        return(1);
-
-    /* not in the list, set insertion point... */
-    *pos = (cmp < 0) ? lo : lo + 1;
+    *pos = lo;
     return(0);
 } /* locateInStringList */
 
@@ -1506,11 +1499,8 @@ static void enumFilesCallback(void *data, const char *origdir, const char *str)
      *  alphabetically...
      */
     pos = pecd->size;
-    if (pos > 0)
-    {
-        if (locateInStringList(str, pecd->list, &pos))
-            return;  /* already in the list. */
-    } /* if */
+    if (locateInStringList(str, pecd->list, &pos))
+        return;  /* already in the list. */
 
     ptr = allocator.Realloc(pecd->list, (pecd->size + 2) * sizeof (char *));
     newstr = (char *) allocator.Malloc(strlen(str) + 1);