Alexandre Julliard : msvcrt: Reimplement strcmp/strncmp to get consistent return values.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 97425bd9639578c397f260d5c745a73f0964406a
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=97425bd9639578c397f260d5c745a73f0964406a

Author: Alexandre Julliard <julliard at winehq.org>
Date:   Thu Oct 31 09:35:40 2019 +0100

msvcrt: Reimplement strcmp/strncmp to get consistent return values.

The system functions may not always return -1 or 1.

Signed-off-by: Alexandre Julliard <julliard at winehq.org>

---

 dlls/msvcrt/cpp.c    |  2 +-
 dlls/msvcrt/mbcs.c   |  4 ++--
 dlls/msvcrt/msvcrt.h |  2 ++
 dlls/msvcrt/string.c | 15 +++++++++++----
 4 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/dlls/msvcrt/cpp.c b/dlls/msvcrt/cpp.c
index a1826a9b1a..404aa1146e 100644
--- a/dlls/msvcrt/cpp.c
+++ b/dlls/msvcrt/cpp.c
@@ -2075,7 +2075,7 @@ int CDECL MSVCRT_type_info_compare(const type_info140 *l, const type_info140 *r)
     int ret;
 
     if (l == r) ret = 0;
-    else ret = strcmp(l->mangled + 1, r->mangled + 1);
+    else ret = MSVCRT_strcmp(l->mangled + 1, r->mangled + 1);
     TRACE("(%p %p) returning %d\n", l, r, ret);
     return ret;
 }
diff --git a/dlls/msvcrt/mbcs.c b/dlls/msvcrt/mbcs.c
index 526ae9b9b5..770ee672af 100644
--- a/dlls/msvcrt/mbcs.c
+++ b/dlls/msvcrt/mbcs.c
@@ -118,7 +118,7 @@ static inline unsigned char* u_strncat( unsigned char* dst, const unsigned char*
 
 static inline int u_strcmp( const unsigned char *s1, const unsigned char *s2 )
 {
-  return strcmp( (const char*)s1, (const char*)s2 );
+  return MSVCRT_strcmp( (const char*)s1, (const char*)s2 );
 }
 
 static inline int u_strcasecmp( const unsigned char *s1, const unsigned char *s2 )
@@ -128,7 +128,7 @@ static inline int u_strcasecmp( const unsigned char *s1, const unsigned char *s2
 
 static inline int u_strncmp( const unsigned char *s1, const unsigned char *s2, MSVCRT_size_t len )
 {
-  return strncmp( (const char*)s1, (const char*)s2, len );
+  return MSVCRT_strncmp( (const char*)s1, (const char*)s2, len );
 }
 
 static inline int u_strncasecmp( const unsigned char *s1, const unsigned char *s2, MSVCRT_size_t len )
diff --git a/dlls/msvcrt/msvcrt.h b/dlls/msvcrt/msvcrt.h
index bfc084425f..d984ab0efd 100644
--- a/dlls/msvcrt/msvcrt.h
+++ b/dlls/msvcrt/msvcrt.h
@@ -1176,6 +1176,8 @@ int __cdecl      MSVCRT__stricmp(const char*, const char*);
 int __cdecl      MSVCRT__strnicmp(const char*, const char*, MSVCRT_size_t);
 int __cdecl      MSVCRT__strnicoll_l(const char*, const char*, MSVCRT_size_t, MSVCRT__locale_t);
 int __cdecl      MSVCRT__strncoll_l(const char*, const char*, MSVCRT_size_t, MSVCRT__locale_t);
+int __cdecl      MSVCRT_strncmp(const char*, const char*, MSVCRT_size_t);
+int __cdecl      MSVCRT_strcmp(const char*, const char*);
 char* __cdecl    MSVCRT_strstr(const char*, const char*);
 unsigned int __cdecl MSVCRT__get_output_format(void);
 char* __cdecl MSVCRT_strtok_s(char*, const char*, char**);
diff --git a/dlls/msvcrt/string.c b/dlls/msvcrt/string.c
index 4ae523cece..346cba7e72 100644
--- a/dlls/msvcrt/string.c
+++ b/dlls/msvcrt/string.c
@@ -616,7 +616,7 @@ int CDECL MSVCRT_strcoll_l( const char* str1, const char* str2, MSVCRT__locale_t
         locinfo = locale->locinfo;
 
     if(!locinfo->lc_handle[MSVCRT_LC_COLLATE])
-        return strcmp(str1, str2);
+        return MSVCRT_strcmp(str1, str2);
     return CompareStringA(locinfo->lc_handle[MSVCRT_LC_COLLATE], 0, str1, -1, str2, -1)-CSTR_EQUAL;
 }
 
@@ -667,7 +667,7 @@ int CDECL MSVCRT__strncoll_l( const char* str1, const char* str2, MSVCRT_size_t
         locinfo = locale->locinfo;
 
     if(!locinfo->lc_handle[MSVCRT_LC_COLLATE])
-        return strncmp(str1, str2, count);
+        return MSVCRT_strncmp(str1, str2, count);
     return CompareStringA(locinfo->lc_handle[MSVCRT_LC_COLLATE], 0,
               str1, MSVCRT_strnlen(str1, count),
               str2, MSVCRT_strnlen(str2, count))-CSTR_EQUAL;
@@ -1943,7 +1943,10 @@ void* __cdecl MSVCRT_memchr(const void *ptr, int c, MSVCRT_size_t n)
  */
 int __cdecl MSVCRT_strcmp(const char *str1, const char *str2)
 {
-    return strcmp(str1, str2);
+    while (*str1 && *str1 == *str2) { str1++; str2++; }
+    if (*str1 > *str2) return 1;
+    if (*str1 < *str2) return -1;
+    return 0;
 }
 
 /*********************************************************************
@@ -1951,7 +1954,11 @@ int __cdecl MSVCRT_strcmp(const char *str1, const char *str2)
  */
 int __cdecl MSVCRT_strncmp(const char *str1, const char *str2, MSVCRT_size_t len)
 {
-    return strncmp(str1, str2, len);
+    if (!len) return 0;
+    while (--len && *str1 && *str1 == *str2) { str1++; str2++; }
+    if (*str1 > *str2) return 1;
+    if (*str1 < *str2) return -1;
+    return 0;
 }
 
 /*********************************************************************