read-cache: optionally disallow NTFS .git variants

diff --git a/wrapper.c b/wrapper.c
index 6a015de5f0564e1ccc9c8cffca891f4ddf4a3ac3..9a6aaafaf35bbd6d2a7a97589edfd9b0b12102c7 100644 (file)
--- a/wrapper.c
+++ b/wrapper.c
@@ -130,6 +130,14 @@ void *xcalloc(size_t nmemb, size_t size)
        return ret;
 }
 
+/*
+ * Limit size of IO chunks, because huge chunks only cause pain.  OS X
+ * 64-bit is buggy, returning EINVAL if len >= INT_MAX; and even in
+ * the absense of bugs, large chunks can result in bad latencies when
+ * you decide to kill the process.
+ */
+#define MAX_IO_SIZE (8*1024*1024)
+
 /*
  * xread() is the same a read(), but it automatically restarts read()
  * operations with a recoverable error (EAGAIN and EINTR). xread()
@@ -138,6 +146,8 @@ void *xcalloc(size_t nmemb, size_t size)
 ssize_t xread(int fd, void *buf, size_t len)
 {
        ssize_t nr;
+       if (len > MAX_IO_SIZE)
+           len = MAX_IO_SIZE;
        while (1) {
                nr = read(fd, buf, len);
                if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
@@ -154,6 +164,8 @@ ssize_t xread(int fd, void *buf, size_t len)
 ssize_t xwrite(int fd, const void *buf, size_t len)
 {
        ssize_t nr;
+       if (len > MAX_IO_SIZE)
+           len = MAX_IO_SIZE;
        while (1) {
                nr = write(fd, buf, len);
                if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
@@ -348,10 +360,12 @@ int git_mkstemp_mode(char *pattern, int mode)
        return git_mkstemps_mode(pattern, 0, mode);
 }
 
+#ifdef NO_MKSTEMPS
 int gitmkstemps(char *pattern, int suffix_len)
 {
        return git_mkstemps_mode(pattern, suffix_len, 0600);
 }
+#endif
 
 int xmkstemp_mode(char *template, int mode)
 {