1 files changed, 143 insertions, 0 deletions
diff --git a/test/rampstream.c b/test/rampstream.c
new file mode 100644
index 0000000..8d81296
--- /dev/null
+++ b/test/rampstream.c
@@ -0,0 +1,143 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+/* rampstream - Generate a check and stream of bytes in a ramp pattern
+ *
+ * Copyright Red Hat
+ * Author: David Gibson <david@gibson.dropbear.id.au>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+
+/* Length of the repeating ramp.  This is a deliberately not a "round" number so
+ * that we're very likely to misalign with likely block or chunk sizes of the
+ * transport.  That means we'll detect gaps in the stream, even if they occur
+ * neatly on block boundaries.  Specifically this is the largest 8-bit prime. */
+#define RAMPLEN		251
+
+#define INTERVAL	10000
+
+#define	ARRAY_SIZE(a)	((int)(sizeof(a) / sizeof((a)[0])))
+
+#define die(...)						\
+	do {							\
+		fprintf(stderr, "rampstream: " __VA_ARGS__);	\
+		exit(1);					\
+	} while (0)
+
+static void usage(void)
+{
+	die("Usage:\n"
+	    "  rampstream send <number>\n"
+	    "    Generate a ramp pattern of bytes on stdout, repeated <number>\n"
+	    "    times\n"
+	    "  rampstream check <number>\n"
+	    "    Check a ramp pattern of bytes on stdin, repeater <number>\n"
+	    "    times\n");
+}
+
+static void ramp_send(unsigned long long num, const uint8_t *ramp)
+{
+	unsigned long long i;
+
+	for (i = 0; i < num; i++) {
+		int off = 0;
+		ssize_t rc;
+
+		if (i % INTERVAL == 0)
+			fprintf(stderr, "%llu...\r", i);
+
+		while (off < RAMPLEN) {
+			rc = write(1, ramp + off, RAMPLEN - off);
+			if (rc < 0) {
+				if (errno == EINTR ||
+				    errno == EAGAIN ||
+				    errno == EWOULDBLOCK)
+					continue;
+				die("Error writing ramp: %s\n",
+				    strerror(errno));
+			}
+			if (rc == 0)
+				die("Zero length write\n");
+			off += rc;
+		}
+	}
+}
+
+static void ramp_check(unsigned long long num, const uint8_t *ramp)
+{
+	unsigned long long i;
+
+	for (i = 0; i < num; i++) {
+		uint8_t buf[RAMPLEN];
+		int off = 0;
+		ssize_t rc;
+
+		if (i % INTERVAL == 0)
+			fprintf(stderr, "%llu...\r", i);
+		
+		while (off < RAMPLEN) {
+			rc = read(0, buf + off, RAMPLEN - off);
+			if (rc < 0) {
+				if (errno == EINTR ||
+				    errno == EAGAIN ||
+				    errno == EWOULDBLOCK)
+					continue;
+				die("Error reading ramp: %s\n",
+				    strerror(errno));
+			}
+			if (rc == 0)
+				die("Unexpected EOF, ramp %llu, byte %d\n",
+				    i, off);
+			off += rc;
+		}
+
+		if (memcmp(buf, ramp, sizeof(buf)) != 0) {
+			int j, k;
+
+			for (j = 0; j < RAMPLEN; j++)
+				if (buf[j] != ramp[j])
+					break;
+			for (k = j; k < RAMPLEN && k < j + 16; k++)
+				fprintf(stderr,
+					"Byte %d: expected 0x%02x, got 0x%02x\n",
+					k, ramp[k], buf[k]);
+			die("Data mismatch, ramp %llu, byte %d\n", i, j);
+		}
+	}
+}
+
+int main(int argc, char *argv[])
+{
+	const char *subcmd = argv[1];
+	unsigned long long num;
+	uint8_t ramp[RAMPLEN];
+	char *e;
+	int i;
+
+	if (argc < 2)
+		usage();
+
+	errno = 0;
+	num = strtoull(argv[2], &e, 0);
+	if (*e || errno)
+		usage();
+
+	/* Initialize the ramp block */
+	for (i = 0; i < RAMPLEN; i++)
+		ramp[i] = i;
+
+	if (strcmp(subcmd, "send") == 0)
+		ramp_send(num, ramp);
+	else if (strcmp(subcmd, "check") == 0)
+		ramp_check(num, ramp);
+	else
+		usage();
+
+	exit(0);
+}