Add puzzles CGI

I just realized I don't need this to be a CGI.

src/puzzles.cgi.c

@@ -0,0 +1,157 @@
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include "common.h"
+
+int
+longcmp(long *a, long *b)
+{
+  if (*a < *b) return -1;
+  if (*a > *b) return 1;
+  return 0;
+}
+
+#define PUZZLES_MAX 500
+
+/** Keeps track of the most points yet awarded in each category */
+struct {
+  char cat[CAT_MAX];
+  long points;
+} points_by_cat[100];
+int ncats = 0;
+
+void
+read_points_by_cat()
+{
+  FILE *f = fopen("/var/lib/ctf/puzzler.log", "r");
+  char  cat[CAT_MAX];
+  long  points;
+  int   i;
+
+  if (! f) {
+    return;
+  }
+
+  while (1) {
+    if (2 != fscanf(f, "%*s %s %ld\n", &cat, &points)) {
+      break;
+    }
+    for (i = 0; i < ncats; i += 1) {
+      if (0 == strcmp(cat, points_by_cat[i].cat)) break;
+    }
+    if (i == ncats) {
+      strcpy(points_by_cat[i].cat, cat);
+      ncats += 1;
+    }
+    if (points > points_by_cat[i].points) {
+      points_by_cat[i].points = points;
+    }
+  }
+}
+
+int
+main(int argc, char *argv[])
+{
+  int i;
+  DIR *srv;
+
+#if 0
+  if (! cgi_init()) {
+    return 0;
+  }
+#endif
+
+  read_points_by_cat();
+
+#if 0
+  for (i = 0; i < ncats; i += 1) {
+    printf("%s: %ld\n", points_by_cat[i].cat, points_by_cat[i].points);
+  }
+#endif
+
+  /* Open /srv/ */
+  srv = opendir("/srv");
+  if (NULL == srv) {
+    cgi_error("Cannot opendir(\"/srv\")");
+  }
+
+  cgi_head("Open puzzles");
+  printf("<dl>\n");
+
+  /* For each file in /srv/ ... */
+  while (1) {
+    struct dirent *e          = readdir(srv);
+    char          *cat        = e->d_name;
+    DIR           *puzzles;
+    char           path[PATH_MAX];
+    long           catpoints[PUZZLES_MAX];
+    size_t         ncatpoints = 0;
+
+    if (! e) break;
+    if ('.' == cat[0]) continue;
+    /* We have to lstat anyway to see if it's a directory; may as
+       well just barge ahead and watch for errors. */
+
+    /* Open /srv/$cat/puzzles/ */
+    my_snprintf(path, sizeof(path), "/srv/%s/puzzles", cat);
+    puzzles = opendir(path);
+    if (NULL == puzzles) {
+      continue;
+    }
+
+    while (ncatpoints < PUZZLES_MAX) {
+      struct dirent *pe = readdir(puzzles);
+      long           points;
+      char          *p;
+
+      if (! pe) break;
+
+      /* Only do this if it's an int */
+      points = strtol(pe->d_name, &p, 10);
+      if (*p) continue;
+
+      catpoints[ncatpoints++] = points;
+    }
+
+    closedir(puzzles);
+
+    /* Sort points */
+    qsort(catpoints, ncatpoints, sizeof(*catpoints),
+          (int (*)(const void *, const void *))longcmp);
+
+
+    /* Print out point values up to one past the last solved puzzle in
+       this category */
+    {
+      long maxpoints = 0;
+
+      /* Find the most points scored in this category */
+      for (i = 0; i < ncats; i += 1) {
+        if (0 == strcmp(cat, points_by_cat[i].cat)) {
+          maxpoints = points_by_cat[i].points;
+          break;
+        }
+      }
+
+      printf("  <dt>%s</dt>\n", cat);
+      printf("  <dd>\n");
+      for (i = 0; i < ncatpoints; i += 1) {
+        printf("    <a href=\"/puzzles/%s/%d\">%d</a>\n",
+               cat, catpoints[i], catpoints[i]);
+        if (catpoints[i] > maxpoints) break;
+      }
+      printf("  </dd>\n");
+    }
+  }
+
+  closedir(srv);
+
+  printf("</dl>\n");
+  cgi_foot();
+
+  return 0;
+}