Make amalgamtion the default when building.

This way we can support fewer build configurations. Also, remove
all undefined behavior due to use of memcpy with NULL pointers. GCC
was exploiting this to remove NULL checks in some builds.

tools/xxd.c

@@ -1,104 +0,0 @@
-/*
-* Copyright (c) 2020 Calvin Rose
-*
-* Permission is hereby granted, free of charge, to any person obtaining a copy
-* of this software and associated documentation files (the "Software"), to
-* deal in the Software without restriction, including without limitation the
-* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
-* sell copies of the Software, and to permit persons to whom the Software is
-* furnished to do so, subject to the following conditions:
-*
-* The above copyright notice and this permission notice shall be included in
-* all copies or substantial portions of the Software.
-*
-* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
-* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
-* IN THE SOFTWARE.
-*/
-
-/* Simple clone of the xxd tool used at build time. Used to
- * create headers out of source files. Only used for core libraries
- * like the bootstrapping code and the stl. */
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <stdint.h>
-
-#define BUFSIZE 1024
-#define PERLINE 10
-
-int main(int argc, const char **argv) {
-
-    static const char hex[] = "0123456789ABCDEF";
-    char buf[BUFSIZE];
-    size_t bytesRead = 0;
-    int32_t totalRead = 0;
-    int lineIndex = 0;
-    int line = 0;
-
-    if (argc != 4) {
-        fprintf(stderr, "Usage: %s infile outfile symbol\n", argv[0]);
-        return 1;
-    }
-
-    /* Open the files */
-    FILE *in = fopen(argv[1], "rb");
-    FILE *out = fopen(argv[2], "wb");
-
-    /* Check if files open successfully */
-    if (in == NULL) {
-        fprintf(stderr, "Could not open input file %s\n", argv[1]);
-        return 1;
-    } else if (out == NULL) {
-        fprintf(stderr, "Could not open output file %s\n", argv[2]);
-        return 1;
-    }
-
-    /* Write the header */
-    fprintf(out, "/* Auto generated - DO NOT EDIT */\n\n#include <stdint.h>\n\n");
-    fprintf(out, "static const unsigned char bytes_%s[] = {", argv[3]);
-
-    /* Read in chunks from buffer */
-    while ((bytesRead = fread(buf, 1, sizeof(buf), in)) > 0) {
-        size_t i;
-        totalRead += bytesRead;
-        for (i = 0; i < bytesRead; ++i) {
-            int byte = ((uint8_t *)buf) [i];
-
-            /* Write the byte */
-            if (lineIndex++ == 0) {
-                if (line++)
-                    fputc(',', out);
-                fputs("\n    ", out);
-            } else {
-                fputs(", ", out);
-            }
-            fputs("0x", out);
-            fputc(hex[byte >> 4], out);
-            fputc(hex[byte & 0xF], out);
-
-            /* Make line index wrap */
-            if (lineIndex >= PERLINE)
-                lineIndex = 0;
-
-        }
-    }
-
-    /* Write the tail */
-    fputs("\n};\n\n", out);
-
-    fprintf(out, "const unsigned char *%s = bytes_%s;\n\n", argv[3], argv[3]);
-
-    /* Write chunk size */
-    fprintf(out, "int32_t %s_size = %d;\n", argv[3], totalRead);
-
-    /* Close the file handles */
-    fclose(in);
-    fclose(out);
-
-    return 0;
-}