[host] nvfbc: make the downsampleParser available outside of NvFBC

host/src/downsample_parser.c

@@ -0,0 +1,86 @@
+/**
+ * looking glass
+ * copyright © 2017-2023 the looking glass authors
+ * https://looking-glass.io
+ *
+ * this program is free software; you can redistribute it and/or modify it
+ * under the terms of the gnu general public license as published by the free
+ * software foundation; either version 2 of the license, or (at your option)
+ * any later version.
+ *
+ * this program is distributed in the hope that it will be useful, but without
+ * any warranty; without even the implied warranty of merchantability or
+ * fitness for a particular purpose. see the gnu general public license for
+ * more details.
+ *
+ * you should have received a copy of the gnu general public license along
+ * with this program; if not, write to the free software foundation, inc., 59
+ * temple place, suite 330, boston, ma 02111-1307 usa
+ */
+
+#include "downsample_parser.h"
+#include "common/debug.h"
+
+#include <string.h>
+
+Vector downsampleRules = {0};
+
+bool downsampleParser(struct Option * opt, const char * str)
+{
+  if (!str)
+    return false;
+
+  opt->value.x_string = strdup(str);
+
+  if (downsampleRules.data)
+    vector_destroy(&downsampleRules);
+
+  if (!vector_create(&downsampleRules, sizeof(DownsampleRule), 10))
+  {
+    DEBUG_ERROR("Failed to allocate ram");
+    return false;
+  }
+
+  char * tmp   = strdup(str);
+  char * token = strtok(tmp, ",");
+  int count = 0;
+  while(token)
+  {
+    DownsampleRule rule = {0};
+    if (token[0] == '>')
+    {
+      rule.greater = true;
+      ++token;
+    }
+
+    if (sscanf(token, "%ux%u:%ux%u",
+      &rule.x,
+      &rule.y,
+      &rule.targetX,
+      &rule.targetY) != 4)
+    {
+      DEBUG_INFO("Unable to parse downsample rules");
+      return false;
+    }
+
+    rule.id = count++;
+
+    DEBUG_INFO(
+      "Rule %u: %ux%u IF X %s %4u %s Y %s %4u",
+      rule.id,
+      rule.targetX,
+      rule.targetY,
+      rule.greater ? "> "  : "==",
+      rule.x,
+      rule.greater ? "OR " : "AND",
+      rule.greater ? "> "  : "==",
+      rule.y
+    );
+    vector_push(&downsampleRules, &rule);
+
+    token = strtok(NULL, ",");
+  }
+  free(tmp);
+
+  return true;
+}