Clean up ioctl-fs-verity-measure and rename to fsveritymeasure

Signed-off-by: Eric Biggers <ebiggers@google.com>
diff --git a/fsveritymeasure.c b/fsveritymeasure.c
new file mode 100644
index 0000000..0be1c25
--- /dev/null
+++ b/fsveritymeasure.c
@@ -0,0 +1,44 @@
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+
+#include "fsverity_api.h"
+
+static void usage(void)
+{
+	fprintf(stderr,
+"Usage: fsveritymeasure FILE EXPECTED_MEASUREMENT\n"
+"\n"
+"EXPECTED_MEASUREMENT must be a 64-character hex string.\n");
+	exit(2);
+}
+
+int main(int args, char *argv[])
+{
+	int fd, i;
+	unsigned int byte;
+	struct fsverity_root_hash measurement = { 0 };
+
+	if (args != 3 || strlen(argv[2]) != 64)
+		usage();
+
+	for (i = 0; i < 32; i++) {
+		if (sscanf(&argv[2][i*2], "%02x", &byte) != 1)
+			usage();
+		measurement.root_hash[i] = byte;
+	}
+	fd = open(argv[1], O_RDONLY);
+	if (fd < 0) {
+		fprintf(stderr, "Can't open %s: %m\n", argv[1]);
+		return 1;
+	}
+	if (ioctl(fd, FS_IOC_MEASURE_FSVERITY, &measurement)) {
+		fprintf(stderr, "FS_IOC_MEASURE_FSVERITY: %m\n");
+		return 1;
+	}
+	close(fd);
+	return 0;
+}
diff --git a/ioctl-fs-verity-measure.c b/ioctl-fs-verity-measure.c
deleted file mode 100644
index e4bf09e..0000000
--- a/ioctl-fs-verity-measure.c
+++ /dev/null
@@ -1,44 +0,0 @@
-#include <linux/fs.h>
-#include <stdio.h>
-#include <errno.h>
-#include <sys/ioctl.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-
-#include <string.h>
-
-int main(int args, char *argv[])
-{
-  int res, fd, i;
-  struct fsverity_root_hash root_hash;
-
-  if (args != 3 || strlen(argv[2]) != 64) {
-    printf("Usage:\n ioctl-fs-verity [filepath] [root hash in hex; 64 characters]\n");
-    return -EINVAL;
-  }
-
-  fd = open(argv[1], O_RDONLY);	
-
-  if (fd == -1) {
-    printf("Could not open [%s]\n", argv[1]);
-    return -EINVAL;
-  }
-  memset((void*)&root_hash, 0, sizeof(struct fsverity_root_hash));
-  for (i = 0; i < 32; i++) {
-    char hdigit[3] = {0, 0, 0};
-
-    memcpy(hdigit, &argv[2][i*2], 2);
-    res = sscanf(hdigit, "%x", &root_hash.root_hash[i]);
-    if (res != 1)
-      return -EINVAL;
-  }
-  res = ioctl(fd, FS_IOC_MEASURE_FSVERITY, &root_hash);
-  if (res) {
-    printf("ioctl() returned [%d]\n", res);
-    return 1;
-  }
-  close(fd);
-  return 0;
-}