[WIP 2/3] cli/insert: move several file/directory manipulation routines into a new util file.

[David Bremner <david@tethera.net>]

This will promote code sharing of low level file operations.
---
 notmuch-insert.c    | 79 ++----------------------------------------
 util/Makefile.local |  1 +
 util/file-util.c    | 98 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 util/file-util.h    | 20 +++++++++++
 4 files changed, 121 insertions(+), 77 deletions(-)
 create mode 100644 util/file-util.c
 create mode 100644 util/file-util.h

diff --git a/notmuch-insert.c b/notmuch-insert.c
index 5ef6e66..48bdd28 100644
--- a/notmuch-insert.c
+++ b/notmuch-insert.c
@@ -23,6 +23,7 @@
 
 #include "notmuch-client.h"
 #include "tag-util.h"
+#include "file-util.h"
 
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -63,26 +64,6 @@ safe_gethostname (char *hostname, size_t len)
     }
 }
 
-/* Call fsync() on a directory path. */
-static notmuch_bool_t
-sync_dir (const char *dir)
-{
-    int fd, r;
-
-    fd = open (dir, O_RDONLY);
-    if (fd == -1) {
-	fprintf (stderr, "Error: open %s: %s\n", dir, strerror (errno));
-	return FALSE;
-    }
-
-    r = fsync (fd);
-    if (r)
-	fprintf (stderr, "Error: fsync %s: %s\n", dir, strerror (errno));
-
-    close (fd);
-
-    return r == 0;
-}
 
 /*
  * Check the specified folder name does not contain a directory
@@ -92,65 +73,9 @@ sync_dir (const char *dir)
 static notmuch_bool_t
 is_valid_folder_name (const char *folder)
 {
-    const char *p = folder;
-
-    for (;;) {
-	if ((p[0] == '.') && (p[1] == '.') && (p[2] == '\0' || p[2] == '/'))
-	    return FALSE;
-	p = strchr (p, '/');
-	if (!p)
-	    return TRUE;
-	p++;
-    }
+    return ! has_double_dot_component (folder);
 }
 
-/*
- * Make the given directory and its parents as necessary, using the
- * given mode. Return TRUE on success, FALSE otherwise. Partial
- * results are not cleaned up on errors.
- */
-static notmuch_bool_t
-mkdir_recursive (const void *ctx, const char *path, int mode)
-{
-    struct stat st;
-    int r;
-    char *parent = NULL, *slash;
-
-    /* First check the common case: directory already exists. */
-    r = stat (path, &st);
-    if (r == 0) {
-        if (! S_ISDIR (st.st_mode)) {
-	    fprintf (stderr, "Error: '%s' is not a directory: %s\n",
-		     path, strerror (EEXIST));
-	    return FALSE;
-	}
-
-	return TRUE;
-    } else if (errno != ENOENT) {
-	fprintf (stderr, "Error: stat '%s': %s\n", path, strerror (errno));
-	return FALSE;
-    }
-
-    /* mkdir parents, if any */
-    slash = strrchr (path, '/');
-    if (slash && slash != path) {
-	parent = talloc_strndup (ctx, path, slash - path);
-	if (! parent) {
-	    fprintf (stderr, "Error: %s\n", strerror (ENOMEM));
-	    return FALSE;
-	}
-
-	if (! mkdir_recursive (ctx, parent, mode))
-	    return FALSE;
-    }
-
-    if (mkdir (path, mode)) {
-	fprintf (stderr, "Error: mkdir '%s': %s\n", path, strerror (errno));
-	return FALSE;
-    }
-
-    return parent ? sync_dir (parent) : TRUE;
-}
 
 /*
  * Create the given maildir folder, i.e. maildir and its
diff --git a/util/Makefile.local b/util/Makefile.local
index 905f237..8749cfb 100644
--- a/util/Makefile.local
+++ b/util/Makefile.local
@@ -5,6 +5,7 @@ extra_cflags += -I$(srcdir)/$(dir)
 
 libutil_c_srcs := $(dir)/xutil.c $(dir)/error_util.c $(dir)/hex-escape.c \
 		  $(dir)/string-util.c $(dir)/talloc-extra.c $(dir)/zlib-extra.c \
+		  $(dir)/file-util.c \
 		$(dir)/util.c
 
 libutil_modules := $(libutil_c_srcs:.c=.o)
diff --git a/util/file-util.c b/util/file-util.c
new file mode 100644
index 0000000..66c4485
--- /dev/null
+++ b/util/file-util.c
@@ -0,0 +1,98 @@
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <talloc.h>
+#include <unistd.h>
+
+#include "file-util.h"
+
+/*
+ * Check whether specified path name contains a directory
+ * component "..". to prevent writes outside of the Maildir
+ */
+int
+has_double_dot_component (const char *path)
+{
+    const char *p = path;
+
+    for (;;) {
+	if ((p[0] == '.') && (p[1] == '.') && (p[2] == '\0' || p[2] == '/'))
+	    return TRUE;
+	p = strchr (p, '/');
+	if (!p)
+	    return FALSE;
+	p++;
+    }
+}
+
+/*
+ * Make the given directory and its parents as necessary, using the
+ * given mode. return TRUE on success, 0 otherwise. Partial
+ * results are not cleaned up on errors.
+ */
+int
+mkdir_recursive (const void *ctx, const char *path, int mode)
+{
+    struct stat st;
+    int r;
+    char *parent = NULL, *slash;
+
+    /* First check the common case: directory already exists. */
+    r = stat (path, &st);
+    if (r == 0) {
+        if (! S_ISDIR (st.st_mode)) {
+	    fprintf (stderr, "Error: '%s' is not a directory: %s\n",
+		     path, strerror (EEXIST));
+	    return FALSE;
+	}
+
+	return TRUE;
+    } else if (errno != ENOENT) {
+	fprintf (stderr, "Error: stat '%s': %s\n", path, strerror (errno));
+	return FALSE;
+    }
+
+    /* mkdir parents, if any */
+    slash = strrchr (path, '/');
+    if (slash && slash != path) {
+	parent = talloc_strndup (ctx, path, slash - path);
+	if (! parent) {
+	    fprintf (stderr, "Error: %s\n", strerror (ENOMEM));
+	    return FALSE;
+	}
+
+	if (! mkdir_recursive (ctx, parent, mode))
+	    return FALSE;
+    }
+
+    if (mkdir (path, mode)) {
+	fprintf (stderr, "Error: mkdir '%s': %s\n", path, strerror (errno));
+	return FALSE;
+    }
+
+    return parent ? sync_dir (parent) : TRUE;
+}
+
+/* Call fsync() on a directory path. */
+int
+sync_dir (const char *dir)
+{
+    int fd, r;
+
+    fd = open (dir, O_RDONLY);
+    if (fd == -1) {
+	fprintf (stderr, "Error: open %s: %s\n", dir, strerror (errno));
+	return FALSE;
+    }
+
+    r = fsync (fd);
+    if (r)
+	fprintf (stderr, "Error: fsync %s: %s\n", dir, strerror (errno));
+
+    close (fd);
+
+    return r == 0;
+}
diff --git a/util/file-util.h b/util/file-util.h
new file mode 100644
index 0000000..4f96957
--- /dev/null
+++ b/util/file-util.h
@@ -0,0 +1,20 @@
+#ifndef _FILE_UTIL_H
+#define _FILE_UTIL_H
+
+#ifndef FALSE 
+#define FALSE 0
+#endif
+#ifndef TRUE
+#define TRUE 1
+#endif
+
+int
+has_double_dot_component (const char *path);
+
+int
+mkdir_recursive (const void *ctx, const char *path, int mode);
+
+int
+sync_dir (const char *path);
+
+#endif
-- 
2.1.0