cryptutils

alder32: Add alder32 utility

Diffstat

3 files changed, 109 insertions, 1 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3f4ab93..ace588c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -16,4 +16,5 @@ ADD_LIBRARY(lib STATIC ${LIBSRC})
 
 LINK_LIBRARIES(lib)
 
-ADD_EXECUTABLE(crc32 ${PROJECT_SOURCE_DIR}/src/crc32.c)
+ADD_EXECUTABLE(alder32 ${PROJECT_SOURCE_DIR}/src/alder32.c)
+ADD_EXECUTABLE(crc32   ${PROJECT_SOURCE_DIR}/src/crc32.c)
diff --git a/README.md b/README.md
index 977151c..433b85c 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,7 @@ OMKOV cryptutils implements many cryptographic utilities.
 
 | Utility          | Description                              | Standard |
 | ---------------- | ---------------------------------------- | -------- |
+| alder32          | Compute the Alder-32 for a file          |          |
 | crc32            | Compute the CRC-32 for a file            |          |
 
 ## Build Instructions
diff --git a/src/alder32.c b/src/alder32.c
new file mode 100644
index 0000000..0f9e468
--- /dev/null
+++ b/src/alder32.c
@@ -0,0 +1,106 @@
+// alder32.c, version 1.0.0
+// OMKOV cryptutils alder32
+// Copyright (C) 2020, Jakob Wakeling
+// All rights reserved.
+
+/*
+OMKOV Permissive Licence, version 1.0
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal with
+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:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimers.
+* Redistributions in binary form must reproduce the above copyright notice, this
+  list of conditions and the following disclaimers in the documentation and/or
+  other materials provided with the distribution.
+* Neither the names of the copyright holders, nor the names of its contributors
+  may be used to endorse or promote products derived from this Software without
+  specific prior written permission.
+
+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 COPYRIGHT
+HOLDERS OR CONTRIBUTORS 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 WITH THE SOFTWARE.
+*/
+
+#include "lib/error.c"
+#include "optget.h"
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#define VERSION "1.0.0"
+
+static inline int alder32(const char *file);
+
+static void hlp(void);
+static void ver(void);
+
+int main(int ac, char *av[]) { A0 = av[0];
+	lop_t lops[] = {
+		{ "help",    ARG_NUL, 256 },
+		{ "version", ARG_NUL, 257 },
+		{ NULL, 0, 0 }
+	};
+	
+	opt_t opt = OPTGET_INIT; opt.str = ""; opt.lops = lops; int o;
+	while((o = optget(&opt, av, 1)) != -1) switch (o) {
+	case 256: { hlp(); return 0; }
+	case 257: { ver(); return 0; }
+	default: { return 1; }
+	}
+	
+	bool warned = false;
+	
+	if (opt.ind == ac) { alder32(NULL); }
+	else for (char **p = &av[opt.ind]; *p; ++p) if (alder32(*p)) {
+		warn("%s: %s", *p, serr()); warned = true;
+	}
+	
+	return warned;
+}
+
+static inline int alder32(const char *file) {
+	uint8_t buf[BUFSIZ * 16]; FILE *fi;
+	register size_t fl = 0; register uint32_t a = 1, b = 0;
+	
+	if (!file || (file[0] == '-' && file[1] == 0)) { fi = stdin; }
+	else if (!(fi = fopen(file, "r"))) { return 1; }
+	
+	for (size_t c; (c = fread(buf, 1, sizeof (buf), fi)); fl += c) {
+		for (register size_t i = 0; i != c; ++i) {
+			a = (a + buf[i]) % 65521;
+			b = (b + a) % 65521;
+		}
+	}
+	
+	printf("%X %zu", (b << 16) | a, fl);
+	if (file) { printf(" %s", file); } fputc('\n', stdout);
+	
+	if (fi != stdin) { fclose(fi); } return 0;
+}
+
+static void hlp(void) {
+	puts("alder32 - compute the Alder-32 for a file\n");
+	puts("usage: alder32 [file...]\n");
+	puts("options:");
+	puts("  --help     Display help information");
+	puts("  --version  Display version information");
+	return;
+}
+
+static void ver(void) {
+	puts("OMKOV cryptutils alder32, version " VERSION);
+	puts("Copyright (C) 2020, Jakob Wakeling");
+	puts("All rights reserved.");
+	puts("OMKOV Permissive Licence (https://www.omkov.net/OLPE)");
+	return;
+}