swscale: add sws_free_context()

Merely a convenience wrapper around sws_freeContext(). The name change is for
parity with the other sws_* functions.

Sponsored-by: Sovereign Tech Fund
Signed-off-by: Niklas Haas <git@haasn.dev>

doc/APIchanges

@@ -2,6 +2,9 @@ The last version increases of all libraries were on 2024-03-07
 
 API changes, most recent first:
 
+2024-10-23 - xxxxxxxxxx - lsws 8.7.100 - swscale.h
+  Add sws_free_context().
+
 2024-10-23 - xxxxxxxxxx - lavu 59.45.100 - pixfmt.h
   Add AV_PIX_FMT_Y216.
 

libswscale/swscale.h

@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2024 Niklas Haas
  * Copyright (C) 2001-2011 Michael Niedermayer <michaelni@gmx.at>
  *
  * This file is part of FFmpeg.
@@ -78,6 +79,12 @@ const AVClass *sws_get_class(void);
  */
 SwsContext *sws_alloc_context(void);
 
+/**
+ * Free the context and everything associated with it, and write NULL
+ * to the provided pointer.
+ */
+void sws_free_context(SwsContext **ctx);
+
 /* values for the flags, the stuff on the command line is different */
 #define SWS_FAST_BILINEAR     1
 #define SWS_BILINEAR          2

libswscale/utils.c

@@ -2515,6 +2515,16 @@ void sws_freeContext(SwsContext *c)
     av_free(c);
 }
 
+void sws_free_context(SwsContext **pctx)
+{
+    SwsContext *ctx = *pctx;
+    if (!ctx)
+        return;
+
+    sws_freeContext(ctx);
+    *pctx = NULL;
+}
+
 SwsContext *sws_getCachedContext(SwsContext *context, int srcW,
                                  int srcH, enum AVPixelFormat srcFormat,
                                  int dstW, int dstH,

libswscale/version.h

@@ -28,8 +28,8 @@
 
 #include "version_major.h"
 
-#define LIBSWSCALE_VERSION_MINOR   6
-#define LIBSWSCALE_VERSION_MICRO 101
+#define LIBSWSCALE_VERSION_MINOR   7
+#define LIBSWSCALE_VERSION_MICRO 100
 
 #define LIBSWSCALE_VERSION_INT  AV_VERSION_INT(LIBSWSCALE_VERSION_MAJOR, \
                                                LIBSWSCALE_VERSION_MINOR, \