1 files changed, 143 insertions, 0 deletions
diff --git a/src/lib-storage/index/maildir/maildir-filename.c b/src/lib-storage/index/maildir/maildir-filename.c
new file mode 100644
index 0000000..9deba82
--- /dev/null
+++ b/src/lib-storage/index/maildir/maildir-filename.c
@@ -0,0 +1,143 @@
+/* Copyright (c) 2002-2018 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "ioloop.h"
+#include "time-util.h"
+#include "hostpid.h"
+#include "maildir-storage.h"
+#include "maildir-filename.h"
+
+const char *maildir_filename_generate(void)
+{
+	static struct timeval last_tv = { 0, 0 };
+	struct timeval tv;
+
+	/* use secs + usecs to guarantee uniqueness within this process. */
+	if (timeval_cmp(&ioloop_timeval, &last_tv) > 0)
+		tv = ioloop_timeval;
+	else {
+		tv = last_tv;
+		if (++tv.tv_usec == 1000000) {
+			tv.tv_sec++;
+			tv.tv_usec = 0;
+		}
+	}
+	last_tv = tv;
+
+	return t_strdup_printf("%s.M%sP%s.%s",
+			       dec2str(tv.tv_sec), dec2str(tv.tv_usec),
+			       my_pid, my_hostname);
+}
+
+bool maildir_filename_get_size(const char *fname, char type, uoff_t *size_r)
+{
+	uoff_t size = 0;
+
+	for (; *fname != '\0'; fname++) {
+		i_assert(*fname != '/');
+		if (*fname == ',' && fname[1] == type && fname[2] == '=') {
+			fname += 3;
+			break;
+		}
+	}
+
+	if (*fname == '\0')
+		return FALSE;
+
+	while (*fname >= '0' && *fname <= '9') {
+		size = size * 10 + (*fname - '0');
+		fname++;
+	}
+
+	if (*fname != MAILDIR_INFO_SEP &&
+	    *fname != MAILDIR_EXTRA_SEP &&
+	    *fname != '\0')
+		return FALSE;
+
+	*size_r = size;
+	return TRUE;
+}
+
+/* a char* hash function from ASU -- from glib */
+unsigned int ATTR_NO_SANITIZE_INTEGER
+maildir_filename_base_hash(const char *s)
+{
+	unsigned int g, h = 0;
+
+	while (*s != MAILDIR_INFO_SEP && *s != '\0') {
+		i_assert(*s != '/');
+		h = (h << 4) + *s;
+		if ((g = h & 0xf0000000UL) != 0) {
+			h = h ^ (g >> 24);
+			h = h ^ g;
+		}
+
+		s++;
+	}
+
+	return h;
+}
+
+int maildir_filename_base_cmp(const char *fname1, const char *fname2)
+{
+	while (*fname1 == *fname2 && *fname1 != MAILDIR_INFO_SEP &&
+	       *fname1 != '\0') {
+		i_assert(*fname1 != '/');
+		fname1++; fname2++;
+	}
+
+	if ((*fname1 == '\0' || *fname1 == MAILDIR_INFO_SEP) &&
+	    (*fname2 == '\0' || *fname2 == MAILDIR_INFO_SEP))
+		return 0;
+	return *fname1 - *fname2;
+}
+
+static bool maildir_fname_get_usecs(const char *fname, int *usecs_r)
+{
+	int usecs = 0;
+
+	/* Assume we already read the timestamp. Next up is
+	   ".<uniqueness>.<host>". Find usecs inside the uniqueness. */
+	if (*fname != '.')
+		return FALSE;
+
+	fname++;
+	while (*fname != '\0' && *fname != '.' && *fname != MAILDIR_INFO_SEP) {
+		if (*fname++ == 'M') {
+			while (*fname >= '0' && *fname <= '9') {
+				usecs = usecs * 10 + (*fname - '0');
+				fname++;
+			}
+			*usecs_r = usecs;
+			return TRUE;
+		}
+	}
+	return FALSE;
+}
+
+int maildir_filename_sort_cmp(const char *fname1, const char *fname2)
+{
+	const char *s1, *s2;
+	time_t secs1 = 0, secs2 = 0;
+	int ret, usecs1, usecs2;
+
+	/* sort primarily by the timestamp in file name */
+	for (s1 = fname1; *s1 >= '0' && *s1 <= '9'; s1++)
+		secs1 = secs1 * 10 + (*s1 - '0');
+	for (s2 = fname2; *s2 >= '0' && *s2 <= '9'; s2++)
+		secs2 = secs2 * 10 + (*s2 - '0');
+
+	ret = (int)((long)secs1 - (long)secs2);
+	if (ret == 0) {
+		/* sort secondarily by microseconds, if they exist */
+		if (maildir_fname_get_usecs(s1, &usecs1) &&
+		    maildir_fname_get_usecs(s2, &usecs2))
+			ret = usecs1 - usecs2;
+
+		if (ret == 0) {
+			/* fallback to comparing the base file name */
+			ret = maildir_filename_base_cmp(s1, s2);
+		}
+	}
+	return ret;
+}