1 files changed, 221 insertions, 0 deletions
diff --git a/sway/base64.c b/sway/base64.c
new file mode 100644
index 00000000..0d51b5c7
--- /dev/null
+++ b/sway/base64.c
@@ -0,0 +1,221 @@
+/*
+ * Adapted from https://github.com/littlstar/b64.c
+ * License under the MIT License:
+ * Copyright (c) 2014 Little Star Media, Inc.
+ *
+ * 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.
+ */
+
+#include <ctype.h>
+#include <stdlib.h>
+#include "util.h"
+
+static const char b64_table[] = {
+	'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
+	'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
+	'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
+	'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
+	'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
+	'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
+	'w', 'x', 'y', 'z', '0', '1', '2', '3',
+	'4', '5', '6', '7', '8', '9', '+', '/'
+};
+
+char *b64_encode(const char *src, size_t len, size_t *flen) {
+	int i = 0;
+	int j = 0;
+	char *enc = NULL;
+	size_t size = len * 4 / 3;
+	size_t idx = 0;
+	unsigned char buf[4];
+	char tmp[3];
+
+	// alloc
+	enc = (char *) malloc(size + 1);
+	if (NULL == enc) { return NULL; }
+
+	// parse until end of source
+	while (len--) {
+		// read up to 3 bytes at a time into `tmp'
+		tmp[i++] = *(src++);
+
+		// if 3 bytes read then encode into `buf'
+		if (3 == i) {
+			buf[0] = (tmp[0] & 0xfc) >> 2;
+			buf[1] = ((tmp[0] & 0x03) << 4) + ((tmp[1] & 0xf0) >> 4);
+			buf[2] = ((tmp[1] & 0x0f) << 2) + ((tmp[2] & 0xc0) >> 6);
+			buf[3] = tmp[2] & 0x3f;
+
+			// shouldn't really happen
+			if (idx + 4 > size) {
+				size += 16;
+				enc = (char *) realloc(enc, size + 1);
+			}
+			for (i = 0; i < 4; ++i) {
+				enc[idx++] = b64_table[buf[i]];
+			}
+
+			// reset index
+			i = 0;
+		}
+	}
+
+	// remainder
+	if (i > 0) {
+		// fill `tmp' with `\0' at most 3 times
+		for (j = i; j < 3; ++j) {
+			tmp[j] = '\0';
+		}
+
+		// perform same codec as above
+		buf[0] = (tmp[0] & 0xfc) >> 2;
+		buf[1] = ((tmp[0] & 0x03) << 4) + ((tmp[1] & 0xf0) >> 4);
+		buf[2] = ((tmp[1] & 0x0f) << 2) + ((tmp[2] & 0xc0) >> 6);
+		buf[3] = tmp[2] & 0x3f;
+
+		// perform same write to `enc` with new allocation
+		size_t delta = (i > 3 ? 0 : 3 - i) + (j > i + 1 ? 0 : i + 1 - j);
+		if (idx + delta > size) {
+			size += delta;
+			enc = (char *) realloc(enc, size + 1);
+		}
+		for (j = 0; (j < i + 1); ++j) {
+			enc[idx++] = b64_table[buf[j]];
+		}
+
+		// while there is still a remainder
+		// append `=' to `enc'
+		while ((i++ < 3)) {
+			enc[idx++] = '=';
+		}
+	}
+
+	enc[idx] = '\0';
+
+	if (flen)
+		*flen = size;
+	return enc;
+}
+
+unsigned char *b64_decode(const char *src, size_t len, size_t *decsize) {
+	int i = 0;
+	int j = 0;
+	int l = 0;
+	// max size estimate
+	size_t size = len * 3 / 4;
+	size_t idx = 0;
+	unsigned char *dec = NULL;
+	unsigned char buf[3];
+	unsigned char tmp[4];
+
+	// alloc
+	dec = (unsigned char *) malloc(size + 1);
+	if (NULL == dec) { return NULL; }
+
+	// parse until end of source
+	while (len--) {
+		if (isspace(src[j])) { j++; continue; }
+		// break if char is `=' or not base64 char
+		if ('=' == src[j]) { break; }
+		if (!(isalnum(src[j]) || '+' == src[j] || '/' == src[j])) { break; }
+
+		// read up to 4 bytes at a time into `tmp'
+		tmp[i++] = src[j++];
+
+		// if 4 bytes read then decode into `buf'
+		if (4 == i) {
+			// translate values in `tmp' from table
+			for (i = 0; i < 4; ++i) {
+				// find translation char in `b64_table'
+				for (l = 0; l < 64; ++l) {
+					if (tmp[i] == b64_table[l]) {
+						tmp[i] = l;
+						break;
+					}
+				}
+			}
+
+			// decode
+			buf[0] = (tmp[0] << 2) + ((tmp[1] & 0x30) >> 4);
+			buf[1] = ((tmp[1] & 0xf) << 4) + ((tmp[2] & 0x3c) >> 2);
+			buf[2] = ((tmp[2] & 0x3) << 6) + tmp[3];
+
+			// unlikely
+			if (idx + 3 > size) {
+				size += 16;
+				dec = (unsigned char *) realloc(dec, size + 1);
+			}
+			if (dec != NULL){
+				for (i = 0; i < 3; ++i) {
+					dec[idx++] = buf[i];
+				}
+			} else {
+				return NULL;
+			}
+
+			// reset
+			i = 0;
+		}
+	}
+
+	// remainder
+	if (i > 0) {
+		// fill `tmp' with `\0' at most 4 times
+		for (j = i; j < 4; ++j) {
+			tmp[j] = '\0';
+		}
+
+		// translate remainder
+		for (j = 0; j < 4; ++j) {
+			// find translation char in `b64_table'
+			for (l = 0; l < 64; ++l) {
+				if (tmp[j] == b64_table[l]) {
+					tmp[j] = l;
+					break;
+				}
+			}
+		}
+
+		// decode remainder
+		buf[0] = (tmp[0] << 2) + ((tmp[1] & 0x30) >> 4);
+		buf[1] = ((tmp[1] & 0xf) << 4) + ((tmp[2] & 0x3c) >> 2);
+		buf[2] = ((tmp[2] & 0x3) << 6) + tmp[3];
+
+		// write remainer decoded buffer to `dec'
+		if (idx + (i - 1) > size) {
+			size += 16;
+			dec = (unsigned char *) realloc(dec, size + 1);
+		}
+		if (dec != NULL){
+			for (j = 0; (j < i - 1); ++j) {
+				dec[idx++] = buf[j];
+			}
+		} else {
+			return NULL;
+		}
+	}
+
+	dec[idx] = '\0';
+	// Return back the size of decoded string if demanded.
+	if (decsize != NULL) {
+		*decsize = size;
+	}
+
+	return dec;
+}