commit files needed for zpm-fetchurl

[zpackage] / crypto / base64.c

diff --git a/crypto/base64.c b/crypto/base64.c
new file mode 100644 (file)
index 0000000..1b944f4
--- /dev/null
+++ b/crypto/base64.c
@@ -0,0 +1,82 @@
+#define _POSIX_C_SOURCE 200809L
+
+#include <stdint.h>
+#include <stdlib.h>
+
+#define WHITESPACE 64
+#define EQUALS     65
+#define INVALID    66
+
+static const unsigned char d[] = {
+       66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 64, 66, 66, 66, 66, 66, 66,
+           66, 66, 66, 66, 66, 66, 66, 66,
+       66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66,
+           66, 62, 66, 66, 66, 63, 52, 53,
+       54, 55, 56, 57, 58, 59, 60, 61, 66, 66, 66, 65, 66, 66, 66, 0, 1,
+           2, 3, 4, 5, 6, 7, 8, 9,
+       10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 66,
+           66, 66, 66, 66, 66, 26, 27, 28,
+       29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45,
+           46, 47, 48, 49, 50, 51, 66, 66,
+       66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66,
+           66, 66, 66, 66, 66, 66, 66, 66,
+       66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66,
+           66, 66, 66, 66, 66, 66, 66, 66,
+       66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66,
+           66, 66, 66, 66, 66, 66, 66, 66,
+       66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66,
+           66, 66, 66, 66, 66, 66, 66, 66,
+       66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66,
+           66, 66, 66, 66, 66, 66, 66, 66,
+       66, 66, 66, 66, 66, 66
+};
+
+int base64decode(const char *in, size_t inLen, unsigned char *out,
+                size_t *outLen) {
+       const char *end = in + inLen;
+       char iter = 0;
+       uint32_t buf = 0;
+       size_t len = 0;
+
+       while (in < end) {
+               unsigned char c = d[(int)(*in++)];
+
+               switch (c) {
+               case WHITESPACE:
+                       continue;       /* skip whitespace */
+               case INVALID:
+                       return 0;       /* invalid input, return error */
+               case EQUALS:    /* pad character, end of data */
+                       in = end;
+                       continue;
+               default:
+                       buf = buf << 6 | c;
+                       iter++; // increment the number of iteration
+                       /* If the buffer is full, split it into bytes */
+                       if (iter == 4) {
+                               if ((len += 3) > *outLen)
+                                       return 0;       /* buffer overflow */
+                               *(out++) = (buf >> 16) & 255;
+                               *(out++) = (buf >> 8) & 255;
+                               *(out++) = buf & 255;
+                               buf = 0;
+                               iter = 0;
+
+                       }
+               }
+       }
+
+       if (iter == 3) {
+               if ((len += 2) > *outLen)
+                       return 0;       /* buffer overflow */
+               *(out++) = (buf >> 10) & 255;
+               *(out++) = (buf >> 2) & 255;
+       } else if (iter == 2) {
+               if (++len > *outLen)
+                       return 0;       /* buffer overflow */
+               *(out++) = (buf >> 4) & 255;
+       }
+
+       *outLen = len;          /* modify to reflect the actual output size */
+       return 1;
+}