bulk upload of source

1 files changed, 96 insertions, 0 deletions

diff --git a/contrib/bootlog_mmap.c b/contrib/bootlog_mmap.c
new file mode 100644
index 0000000..7bd9583
--- /dev/null
+++ b/contrib/bootlog_mmap.c
@@ -0,0 +1,96 @@
+/* bootlog.c */
+/* diet -Os gcc -o bootlog bootlog.c -Wall -W */
+
+#include <unistd.h>
+#include <alloca.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h> /* rename */
+#include <sys/mman.h>
+#include <sys/wait.h>
+#include "../ninitfeatures.h"
+
+static int xx_write(int fd, void *buf, size_t len);
+static int do_io(void *buf, int len);
+static int mk_backup();
+
+struct mem {
+  struct mem *x;
+  unsigned int p;
+};
+
+static struct mem *last, *root;
+static char *flag_rename, *name;
+static int flagstderr, flagstdout, m;
+int fd = -1;
+
+#include "../pagesize_defs.h"
+#define mem_size	sizeof(struct mem)
+#define alloc_size	(page_size - mem_size)
+
+void *mmap_alloc() {
+  struct mem *m;
+  m=mmap(0,page_size,PROT_READ|PROT_WRITE,MAP_ANONYMOUS|MAP_PRIVATE,-1,0);
+  if (m==(struct mem*)-1) return 0;
+  /* kernel must zeroed m->p and m->x */
+
+  if (last) last->x = m;
+  else root = m;
+  last = m;
+  return ((void *)m) + mem_size;
+}
+
+static void flush_root() {
+  if (mk_backup()) return;
+  if (fd < 0) fd = open(name, O_WRONLY | m, 0644);
+  if (fd < 0) return;
+  while (root) {
+    void *x = root->x;
+    xx_write(fd, ((void *)root) + mem_size, root->p);
+    root->p = 0;
+    if (root == last) break;
+    munmap(root, page_size);
+    root = x;
+  }
+}
+
+static void loop(unsigned long len) {
+  char *buf = 0;
+  int r;
+  if (flag_rename) {
+    char *d, *s = name;
+    d = flag_rename = alloca(str_len(name) + 5);
+    while (*s) *d++ = *s++;
+    d[0] = '~';
+    d[1] = 0;
+  }
+  while (len) {
+    if (buf == 0 && (buf=mmap_alloc()) == 0) break;
+
+    if (last->p >= alloc_size) {
+      flush_root();
+      if (last->p) { buf = 0; continue; }
+    }
+
+    r = do_io(buf + last->p, alloc_size - last->p);
+    if (r==0) break;
+    if (r<0) continue;
+
+    if ((unsigned long)r > len) r = len;
+    last->p  += r;
+    len -= r;
+  }
+
+  if (buf==0 || len==0) {
+    char tmp[1024];
+    while (do_io(tmp,sizeof(tmp)));
+  }
+
+  mk_backup();
+  flag_rename = 0;
+  flush_root();
+  fsync(fd);
+  close(fd);
+}
+
+#include "bootlog.h"