scalar-diagnose: move 'get_disk_info()' to 'compat/'

Move 'get_disk_info()' function into 'compat/'. Although Scalar-specific
code is generally not part of the main Git tree, 'get_disk_info()' will be
used in subsequent patches by additional callers beyond 'scalar diagnose'.
This patch prepares for that change, at which point this platform-specific
code should be part of 'compat/' as a matter of convention.

The function is copied *mostly* verbatim, with two exceptions:

* '#ifdef WIN32' is replaced with '#ifdef GIT_WINDOWS_NATIVE' to allow
  'statvfs' to be used with Cygwin.
* the 'struct strbuf buf' and 'int res' (as well as their corresponding
  cleanup & return) are moved outside of the '#ifdef' block.

Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 56 insertions, 0 deletions

diff --git a/compat/disk.h b/compat/disk.h
new file mode 100644
index 0000000..50a32e3
--- /dev/null
+++ b/compat/disk.h
@@ -0,0 +1,56 @@
+#ifndef COMPAT_DISK_H
+#define COMPAT_DISK_H
+
+#include "git-compat-util.h"
+
+static int get_disk_info(struct strbuf *out)
+{
+	struct strbuf buf = STRBUF_INIT;
+	int res = 0;
+
+#ifdef GIT_WINDOWS_NATIVE
+	char volume_name[MAX_PATH], fs_name[MAX_PATH];
+	DWORD serial_number, component_length, flags;
+	ULARGE_INTEGER avail2caller, total, avail;
+
+	strbuf_realpath(&buf, ".", 1);
+	if (!GetDiskFreeSpaceExA(buf.buf, &avail2caller, &total, &avail)) {
+		error(_("could not determine free disk size for '%s'"),
+		      buf.buf);
+		res = -1;
+		goto cleanup;
+	}
+
+	strbuf_setlen(&buf, offset_1st_component(buf.buf));
+	if (!GetVolumeInformationA(buf.buf, volume_name, sizeof(volume_name),
+				   &serial_number, &component_length, &flags,
+				   fs_name, sizeof(fs_name))) {
+		error(_("could not get info for '%s'"), buf.buf);
+		res = -1;
+		goto cleanup;
+	}
+	strbuf_addf(out, "Available space on '%s': ", buf.buf);
+	strbuf_humanise_bytes(out, avail2caller.QuadPart);
+	strbuf_addch(out, '\n');
+#else
+	struct statvfs stat;
+
+	strbuf_realpath(&buf, ".", 1);
+	if (statvfs(buf.buf, &stat) < 0) {
+		error_errno(_("could not determine free disk size for '%s'"),
+			    buf.buf);
+		res = -1;
+		goto cleanup;
+	}
+
+	strbuf_addf(out, "Available space on '%s': ", buf.buf);
+	strbuf_humanise_bytes(out, (off_t)stat.f_bsize * (off_t)stat.f_bavail);
+	strbuf_addf(out, " (mount flags 0x%lx)\n", stat.f_flag);
+#endif
+
+cleanup:
+	strbuf_release(&buf);
+	return res;
+}
+
+#endif /* COMPAT_DISK_H */