- a tiny, but useful function

[packages/sqlite3.git] / sqlite3-sign-function.patch

diff -uNr sqlite-3.2.7.orig/src/func.c sqlite-3.2.7/src/func.c
--- sqlite-3.2.7.orig/src/func.c	2005-09-17 18:34:55.000000000 +0200
+++ sqlite-3.2.7/src/func.c	2005-10-17 00:11:22.000000000 +0200
@@ -139,6 +139,31 @@
 }
 
 /*
+** Implementation of the sign() function
+*/
+static void signFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
+  assert( argc==1 );
+  switch( sqlite3_value_type(argv[0]) ){
+    case SQLITE_INTEGER: {
+      i64 iVal = sqlite3_value_int64(argv[0]);
+      iVal = (iVal > 0)? 1 : (iVal < 0)? -1 : 0;
+      sqlite3_result_int64(context, iVal);
+      break;
+    }
+    case SQLITE_NULL: {
+      sqlite3_result_null(context);
+      break;
+    }
+    default: {
+      double rVal = sqlite3_value_double(argv[0]);
+      rVal = (rVal > 0)? 1.0 : (rVal < 0)? -1.0 : 0;
+      sqlite3_result_double(context, rVal);
+      break;
+    }
+  }
+}
+
+/*
 ** Implementation of the substr() function
 */
 static void substrFunc(
@@ -963,6 +988,7 @@
     { "substr",             3, 0, SQLITE_UTF16LE, 0, sqlite3utf16Substr },
 #endif
     { "abs",                1, 0, SQLITE_UTF8,    0, absFunc    },
+	{ "sign",               1, 0, SQLITE_UTF8,    0, signFunc   },
     { "round",              1, 0, SQLITE_UTF8,    0, roundFunc  },
     { "round",              2, 0, SQLITE_UTF8,    0, roundFunc  },
     { "upper",              1, 0, SQLITE_UTF8,    0, upperFunc  },