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-rw-r--r--src/erasure-code/jerasure/gf-complete/tools/gf_mult.c68
1 files changed, 68 insertions, 0 deletions
diff --git a/src/erasure-code/jerasure/gf-complete/tools/gf_mult.c b/src/erasure-code/jerasure/gf-complete/tools/gf_mult.c
new file mode 100644
index 000000000..815bd8b26
--- /dev/null
+++ b/src/erasure-code/jerasure/gf-complete/tools/gf_mult.c
@@ -0,0 +1,68 @@
+/*
+ * GF-Complete: A Comprehensive Open Source Library for Galois Field Arithmetic
+ * James S. Plank, Ethan L. Miller, Kevin M. Greenan,
+ * Benjamin A. Arnold, John A. Burnum, Adam W. Disney, Allen C. McBride.
+ *
+ * gf_mult.c
+ *
+ * Multiplies two numbers in gf_2^w
+ */
+
+#include <stdio.h>
+#include <getopt.h>
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "gf_complete.h"
+#include "gf_method.h"
+#include "gf_general.h"
+
+void usage(int why)
+{
+ fprintf(stderr, "usage: gf_mult a b w [method] - does multiplication of a and b in GF(2^w)\n");
+ if (why == 'W') {
+ fprintf(stderr, "Bad w.\n");
+ fprintf(stderr, "Legal w are: 1 - 32, 64 and 128.\n");
+ fprintf(stderr, "Append 'h' to w to treat a, b and the product as hexadecimal.\n");
+ fprintf(stderr, "w=128 is hex only (i.e. '128' will be an error - do '128h')\n");
+ }
+ if (why == 'A') fprintf(stderr, "Bad a\n");
+ if (why == 'B') fprintf(stderr, "Bad b\n");
+ if (why == 'M') {
+ fprintf(stderr, "Bad Method Specification: ");
+ gf_error();
+ }
+ exit(1);
+}
+
+int main(int argc, char **argv)
+{
+ int hex, w;
+ gf_t gf;
+ gf_general_t a, b, c;
+ char output[50];
+
+ if (argc < 4) usage(' ');
+
+ if (sscanf(argv[3], "%d", &w) == 0) usage('W');
+ if (w <= 0 || (w > 32 && w != 64 && w != 128)) usage('W');
+
+ hex = (strchr(argv[3], 'h') != NULL);
+ if (!hex && w == 128) usage('W');
+
+ if (argc == 4) {
+ if (gf_init_easy(&gf, w) == 0) usage('M');
+ } else {
+ if (create_gf_from_argv(&gf, w, argc, argv, 4) == 0) usage('M');
+ }
+
+ if (!gf_general_s_to_val(&a, w, argv[1], hex)) usage('A');
+ if (!gf_general_s_to_val(&b, w, argv[2], hex)) usage('B');
+
+ gf_general_multiply(&gf, &a, &b, &c);
+ gf_general_val_to_s(&c, w, output, hex);
+
+ printf("%s\n", output);
+ exit(0);
+}