Move oniguruma and decNumber to vendor directory (#3234)

vendor/decNumber/example4.c

@@ -0,0 +1,61 @@
+/* ------------------------------------------------------------------ */
+/* Decimal Number Library Demonstration program                       */
+/* ------------------------------------------------------------------ */
+/* Copyright (c) IBM Corporation, 2001.  All rights reserved.         */
+/* ----------------------------------------------------------------+- */
+/*                                                 right margin -->|  */
+
+// example4.c -- add two numbers, active error handling
+// Arguments are two numbers
+
+#define  DECNUMDIGITS 38           // work with up to 38 digits
+#include "decNumber.h"             // base number library
+#include <stdio.h>                 // for printf
+
+// [snip...
+#include <signal.h>                // signal handling
+#include <setjmp.h>                // setjmp/longjmp
+
+jmp_buf preserve;                  // stack snapshot
+
+void signalHandler(int);           // prototype for GCC
+void signalHandler(int sig) {
+  signal(SIGFPE, signalHandler);   // re-enable
+  longjmp(preserve, sig);          // branch to preserved point
+  }
+// ...snip]
+int main(int argc, char *argv[]) {
+  decNumber a, b;                  // working numbers
+  decContext set;                  // working context
+  char string[DECNUMDIGITS+14];    // conversion buffer
+  int value;                       // work variable
+
+  if (argc<3) {                    // not enough words
+    printf("Please supply two numbers to add.\n");
+    return 1;
+    }
+  decContextDefault(&set, DEC_INIT_BASE);    // initialize
+
+// [snip...
+  signal(SIGFPE, signalHandler);   // set up signal handler
+  value=setjmp(preserve);          // preserve and test environment
+  if (value) {                     // (non-0 after longjmp)
+    set.status &= DEC_Errors;      // keep only errors
+    printf("Signal trapped [%s].\n", decContextStatusToString(&set));
+    return 1;
+    }
+// ...snip]
+
+// [change from Example 1, here]
+  // leave traps enabled
+  set.digits=DECNUMDIGITS;         // set precision
+
+  decNumberFromString(&a, argv[1], &set);
+  decNumberFromString(&b, argv[2], &set);
+
+  decNumberAdd(&a, &a, &b, &set);            // A=A+B
+  decNumberToString(&a, string);
+
+  printf("%s + %s => %s\n", argv[1], argv[2], string);
+  return 0;
+  } // main