add scr_print binary

This adds an scr_print binary, which is essentially a duplicate of the
kvtree_print command. This separate binary abstracts the fact from
users that SCR files are really stored as kvtree files.

src/CMakeLists.txt

@@ -126,6 +126,7 @@ LIST(APPEND cliscr_c_bins
 	scr_index
         scr_rebuild_xor
         scr_rebuild_partner
+	scr_print
 )
 
 # CLI binaries that require full SCR library

src/scr_print.c

@@ -0,0 +1,102 @@
+#include "kvtree.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <string.h>
+#include <errno.h>
+#include <getopt.h>
+
+static void print_usage(void)
+{
+  printf("\n");
+  printf("Usage: scr_print [options] <file>\n");
+  printf("\n");
+  printf("  Options:\n");
+  printf("    -m, --mode <mode>  Specify print format: \"tree\" or \"keyval\" (default tree)\n");
+  printf("    -h, --help         Print usage\n");
+  printf("\n");
+}
+
+int main(int argc, char* argv[])
+{
+  int rc = 0;
+
+  static const char *opt_string = "m:h";
+  static struct option long_options[] = {
+    {"mode",    required_argument, NULL, 'm'},
+    {"help",    no_argument,       NULL, 'h'},
+    {NULL,      no_argument,       NULL,   0}
+  };
+
+  int usage = 0;
+  char* mode = NULL;
+
+  int long_index = 0;
+  while (1) {
+    char c = getopt_long(argc, argv, opt_string, long_options, &long_index);
+    if (c == -1) {
+      break;
+    }
+
+    switch(c) {
+      case 'm':
+        mode = strdup(optarg);
+        break;
+      case 'h':
+        usage = 1;
+        break;
+      default:
+        printf("ERROR: Unknown option: `%s'\n", argv[optind]);
+        usage = 1;
+        rc = 1;
+        break;
+    }
+  }
+
+  /* check that we were given exactly one filename argument */
+  int numargs = argc - optind;
+  if (!usage && numargs != 1) {
+    printf("ERROR: Missing file name or too many files\n");
+    usage = 1;
+    rc = 1;
+  }
+
+  /* parse the print mode option, if one is given */
+  int print_mode = KVTREE_PRINT_TREE;
+  if (mode != NULL) {
+    if (strcmp(mode, "tree") == 0) {
+      print_mode = KVTREE_PRINT_TREE;
+    } else if (strcmp(mode, "keyval") == 0) {
+      print_mode = KVTREE_PRINT_KEYVAL;
+    } else {
+      printf("ERROR: Invalid mode name: `%s'\n", mode);
+      usage = 1;
+      rc = 1;
+    }
+    free(mode);
+  }
+
+  if (usage) {
+    print_usage();
+    return rc;
+  }
+
+  /* get the file name */
+  char* filename = argv[optind];
+
+  /* read in the file */
+  kvtree* hash = kvtree_new();
+  if (kvtree_read_file(filename, hash) == KVTREE_SUCCESS) {
+    /* we read the file, now print it out */
+    kvtree_print_mode(hash, 0, print_mode);
+  } else {
+    printf("ERROR: Failed to read file: `%s'\n", filename);
+    rc = 1;
+  }
+  kvtree_delete(&hash);
+
+  return rc;
+}