Imported Upstream version 2.0.4

[platform/upstream/git.git] / wrapper.c

diff --git a/wrapper.c b/wrapper.c
index 68739aa..bc1bfb8 100644 (file)
--- a/wrapper.c
+++ b/wrapper.c
@@ -131,6 +131,14 @@ void *xcalloc(size_t nmemb, size_t size)
 }
 
 /*
+ * 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 absence 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()
  * DOES NOT GUARANTEE that "len" bytes is read even if the data is available.
@@ -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))
@@ -162,6 +174,24 @@ ssize_t xwrite(int fd, const void *buf, size_t len)
        }
 }
 
+/*
+ * xpread() is the same as pread(), but it automatically restarts pread()
+ * operations with a recoverable error (EAGAIN and EINTR). xpread() DOES
+ * NOT GUARANTEE that "len" bytes is read even if the data is available.
+ */
+ssize_t xpread(int fd, void *buf, size_t len, off_t offset)
+{
+       ssize_t nr;
+       if (len > MAX_IO_SIZE)
+               len = MAX_IO_SIZE;
+       while (1) {
+               nr = pread(fd, buf, len, offset);
+               if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
+                       continue;
+               return nr;
+       }
+}
+
 ssize_t read_in_full(int fd, void *buf, size_t count)
 {
        char *p = buf;
@@ -202,6 +232,26 @@ ssize_t write_in_full(int fd, const void *buf, size_t count)
        return total;
 }
 
+ssize_t pread_in_full(int fd, void *buf, size_t count, off_t offset)
+{
+       char *p = buf;
+       ssize_t total = 0;
+
+       while (count > 0) {
+               ssize_t loaded = xpread(fd, p, count, offset);
+               if (loaded < 0)
+                       return -1;
+               if (loaded == 0)
+                       return total;
+               count -= loaded;
+               p += loaded;
+               total += loaded;
+               offset += loaded;
+       }
+
+       return total;
+}
+
 int xdup(int fd)
 {
        int ret = dup(fd);
@@ -229,7 +279,7 @@ int xmkstemp(char *template)
                int saved_errno = errno;
                const char *nonrelative_template;
 
-               if (!template[0])
+               if (strlen(template) != strlen(origtemplate))
                        template = origtemplate;
 
                nonrelative_template = absolute_path(template);
@@ -322,7 +372,7 @@ int git_mkstemps_mode(char *pattern, int suffix_len, int mode)
                template[5] = letters[v % num_letters]; v /= num_letters;
 
                fd = open(pattern, O_CREAT | O_EXCL | O_RDWR, mode);
-               if (fd > 0)
+               if (fd >= 0)
                        return fd;
                /*
                 * Fatal error (EPERM, ENOSPC etc).
@@ -348,10 +398,12 @@ 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)
 {
@@ -408,14 +460,28 @@ void warn_on_inaccessible(const char *path)
        warning(_("unable to access '%s': %s"), path, strerror(errno));
 }
 
-int access_or_warn(const char *path, int mode)
+static int access_error_is_ok(int err, unsigned flag)
+{
+       return err == ENOENT || err == ENOTDIR ||
+               ((flag & ACCESS_EACCES_OK) && err == EACCES);
+}
+
+int access_or_warn(const char *path, int mode, unsigned flag)
 {
        int ret = access(path, mode);
-       if (ret && errno != ENOENT)
+       if (ret && !access_error_is_ok(errno, flag))
                warn_on_inaccessible(path);
        return ret;
 }
 
+int access_or_die(const char *path, int mode, unsigned flag)
+{
+       int ret = access(path, mode);
+       if (ret && !access_error_is_ok(errno, flag))
+               die_errno(_("unable to access '%s'"), path);
+       return ret;
+}
+
 struct passwd *xgetpwuid_self(void)
 {
        struct passwd *pw;