From a8e19d5d8057e82cbda2705d755f3d4e1d3da20a Mon Sep 17 00:00:00 2001
From: Andrew Cady <d@jerkface.net>
Date: Sun, 1 May 2016 05:25:14 -0400
Subject: remove references to files outside of this repo

(commit the files into this repo)
---
 src/wait_for_files.c | 114 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 114 insertions(+)
 create mode 100644 src/wait_for_files.c

(limited to 'src/wait_for_files.c')

diff --git a/src/wait_for_files.c b/src/wait_for_files.c
new file mode 100644
index 0000000..3a7f6b5
--- /dev/null
+++ b/src/wait_for_files.c
@@ -0,0 +1,114 @@
+// wait_for_files - Efficiently sleeps until the files specified on the
+// command line exist (or have existed during execution).
+// Linux 2.6.13, GNU C only.  Use gcc -std=c99
+// glibc 2.4 or define PRIVATE_INOTIFY_HEADER
+
+// #define PRIVATE_INOTIFY_HEADER "inotifytools/inotify.h"
+
+#include <errno.h>
+#include <error.h>
+#include <libgen.h>
+#include <stdbool.h>
+#include <string.h>
+#ifdef PRIVATE_INOTIFY_HEADER
+#include PRIVATE_INOTIFY_HEADER
+#else
+#include <sys/inotify.h>
+#endif
+#include <sys/ioctl.h>
+#include <sys/select.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+char *strdup(const char *s); // wtf?
+
+int main(int argc, char **argv)
+{
+  if (argc == 1) return 0;
+  --argc; ++argv;
+
+  int notify = inotify_init();
+  if (notify < 0)
+    error(-1, errno, "inotify_init error");
+
+  struct wdtab_t {
+    char *basename;
+    int wd;		// set to 0 when found
+  } wdtab[argc];
+
+  bool done = true;
+  for (int i = 0; i < argc; ++i) {
+    struct wdtab_t *p = &wdtab[i];
+
+    char *dirname_mem;
+    if (!(dirname_mem = strdup(argv[i])) ||
+	!(p->basename = strdup(argv[i])))
+      error(-1, errno, "strdup error");
+    char *dirname_val = dirname(dirname_mem);
+    p->basename = basename(p->basename);
+
+    p->wd = inotify_add_watch(notify, dirname_val, IN_CREATE|IN_MASK_ADD);
+    if (p->wd < 0)
+      error(-1, errno, "inotify_add_watch error (file: %s)", argv[i]);
+    free(dirname_mem);
+
+    struct stat dummy; 
+    if (stat(argv[i], &dummy) == 0)
+      p->wd = 0;
+    else
+      done = false;
+  }
+  if (done) return 0;
+
+  for (;;) {
+    fd_set rfds;
+    FD_ZERO(&rfds);
+    FD_SET(notify, &rfds);
+    switch (select(notify+1, &rfds, NULL, NULL, NULL)) {
+      case -1: error(-1, errno, "select error");
+      case 0: continue; // this should never happen
+    }
+
+    // is ioctl FIONREAD even documented?
+    int bytes_ready = 0;
+    if (ioctl(notify, FIONREAD, &bytes_ready) < 0)
+      error(-1, errno, "ioctl FIONREAD (inotify) error");
+    if (bytes_ready % sizeof(struct inotify_event) != 0)
+      // this should never ever ever happen, evar
+      error(-1, 0, "ioctl FIONREAD (inotify) returned bizarre result (%i)",
+	    bytes_ready);
+    if (bytes_ready < sizeof(struct inotify_event))
+      continue; // bytes_ready <= 0.  this should never happen
+
+    struct inotify_event evs[bytes_ready / sizeof(struct inotify_event)];
+
+    ssize_t r;
+    if ((r = read(notify, evs, sizeof(evs))) != sizeof(evs)) {
+      if (r < 0)
+	error(-1, errno, "read error (inotify)");
+      else
+	error(1, 0, "short read (inotify, got %i, expected %i)",
+	      (int) r, (int) sizeof(evs));
+    }
+
+    done = true;
+    for (int j = 0; j < sizeof(evs) / sizeof(evs[0]); ++j) {
+      struct inotify_event *ev = &evs[j];
+      for (int i = 0; i < argc; ++i) {
+	struct wdtab_t *p = &wdtab[i];
+	if (!p->wd)
+	  continue;
+	else if ((ev->wd == p->wd) &&
+		 (ev->mask|IN_CREATE) &&
+		 !strcmp(ev->name, p->basename))
+        {
+	  p->wd = 0;
+	} else
+	  done = false;
+      }
+    }
+    if (done) return 0;
+  }
+}
-- 
cgit v1.2.3