libe2p: helpers for configuring the encoding superblock fields

Implement helper functions to convert the encoding name and specific
parameters requested by the user on the command line into the format
that is written to disk.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/lib/e2p/Makefile.in b/lib/e2p/Makefile.in
index 2b0aa1915130d670afdd99b34ee9b9ef53cf03ec..68d534cdaf11ed788d130c282457cb27e6d4c401 100644 (file)
--- a/lib/e2p/Makefile.in
+++ b/lib/e2p/Makefile.in
@@ -19,7 +19,8 @@ all:: e2p.pc
 OBJS=          feature.o fgetflags.o fsetflags.o fgetversion.o fsetversion.o \
                getflags.o getversion.o hashstr.o iod.o ls.o ljs.o mntopts.o \
                parse_num.o pe.o pf.o ps.o setflags.o setversion.o uuid.o \
-               ostype.o percent.o crypto_mode.o fgetproject.o fsetproject.o
+               ostype.o percent.o crypto_mode.o fgetproject.o fsetproject.o \
+               encoding.o
 
 SRCS=          $(srcdir)/feature.c $(srcdir)/fgetflags.c \
                $(srcdir)/fsetflags.c $(srcdir)/fgetversion.c \
@@ -29,7 +30,7 @@ SRCS=         $(srcdir)/feature.c $(srcdir)/fgetflags.c \
                $(srcdir)/pe.c $(srcdir)/pf.c $(srcdir)/ps.c \
                $(srcdir)/setflags.c $(srcdir)/setversion.c $(srcdir)/uuid.c \
                $(srcdir)/ostype.c $(srcdir)/percent.c $(srcdir)/crypto_mode.c \
-               $(srcdir)/fgetproject.c $(srcdir)/fsetproject.c
+               $(srcdir)/fgetproject.c $(srcdir)/fsetproject.c $(srcdir)/encoding.c
 HFILES= e2p.h
 
 LIBRARY= libe2p
@@ -147,6 +148,9 @@ getversion.o: $(srcdir)/getversion.c $(top_builddir)/lib/config.h \
 hashstr.o: $(srcdir)/hashstr.c $(top_builddir)/lib/config.h \
  $(top_builddir)/lib/dirpaths.h $(srcdir)/e2p.h \
  $(top_srcdir)/lib/ext2fs/ext2_fs.h $(top_builddir)/lib/ext2fs/ext2_types.h
+encoding.o: $(srcdir)/encoding.c $(top_builddir)/lib/config.h \
+ $(top_builddir)/lib/dirpaths.h $(srcdir)/e2p.h \
+ $(top_srcdir)/lib/ext2fs/ext2_fs.h $(top_builddir)/lib/ext2fs/ext2_types.h
 iod.o: $(srcdir)/iod.c $(top_builddir)/lib/config.h \
  $(top_builddir)/lib/dirpaths.h $(srcdir)/e2p.h \
  $(top_srcdir)/lib/ext2fs/ext2_fs.h $(top_builddir)/lib/ext2fs/ext2_types.h

diff --git a/lib/e2p/e2p.h b/lib/e2p/e2p.h
index d70b59a5d358de49c6510ee54b2ba998ad8ec051..cc2dbf39bfeb7dba09956e085a4949927b929a80 100644 (file)
--- a/lib/e2p/e2p.h
+++ b/lib/e2p/e2p.h
@@ -80,3 +80,7 @@ unsigned int e2p_percent(int percent, unsigned int base);
 
 const char *e2p_encmode2string(int num);
 int e2p_string2encmode(char *string);
+
+int e2p_str2encoding(const char *string);
+int e2p_get_encoding_flags(int encoding);
+int e2p_str2encoding_flags(int encoding, char *param, __u16 *flags);

diff --git a/lib/e2p/encoding.c b/lib/e2p/encoding.c
new file mode 100644 (file)
index 0000000..8843331
--- /dev/null
+++ b/lib/e2p/encoding.c
@@ -0,0 +1,104 @@
+/*
+ * encoding.c --- convert between encoding magic numbers and strings
+ *
+ * Copyright (C) 2018  Collabora Ltd.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#include "config.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <errno.h>
+#include <stdio.h>
+
+#include "e2p.h"
+
+#define ARRAY_SIZE(array)                      \
+        (sizeof(array) / sizeof(array[0]))
+
+static const struct {
+       char *name;
+       __u16 encoding_magic;
+       __u16 default_flags;
+
+} ext4_encoding_map[] = {
+       {
+               .encoding_magic = EXT4_ENC_ASCII,
+               .name = "ascii",
+               .default_flags = 0
+       },
+       {
+               .encoding_magic = EXT4_ENC_UTF8_11_0,
+               .name = "utf8",
+               .default_flags = (EXT4_UTF8_NORMALIZATION_TYPE_NFKD |
+                                 EXT4_UTF8_CASEFOLD_TYPE_NFKDCF)
+       },
+};
+
+static const struct enc_flags {
+       __u16 flag;
+       char *param;
+} encoding_flags[] = {
+       { EXT4_ENC_STRICT_MODE_FL, "strict" },
+};
+
+/* Return a positive number < 0xff indicating the encoding magic number
+ * or a negative value indicating error. */
+int e2p_str2encoding(const char *string)
+{
+       int i;
+
+       for (i = 0 ; i < ARRAY_SIZE(ext4_encoding_map); i++)
+               if (!strcmp(string, ext4_encoding_map[i].name))
+                       return ext4_encoding_map[i].encoding_magic;
+
+       return -EINVAL;
+}
+
+int e2p_get_encoding_flags(int encoding)
+{
+       int i;
+
+       for (i = 0 ; i < ARRAY_SIZE(ext4_encoding_map); i++)
+               if (ext4_encoding_map[i].encoding_magic == encoding)
+                       return ext4_encoding_map[encoding].default_flags;
+
+       return 0;
+}
+
+int e2p_str2encoding_flags(int encoding, char *param, __u16 *flags)
+{
+       char *f = strtok(param, "-");
+       const struct enc_flags *fl;
+       int i, neg = 0;
+
+       while (f) {
+               neg = 0;
+               if (!strncmp("no", f, 2)) {
+                       neg = 1;
+                       f += 2;
+               }
+
+               for (i = 0; i < ARRAY_SIZE(encoding_flags); i++) {
+                       fl = &encoding_flags[i];
+                       if (!strcmp(fl->param, f)) {
+                               if (neg)
+                                       *flags &= ~fl->flag;
+                               else
+                                       *flags |= fl->flag;
+
+                               goto next_flag;
+                       }
+               }
+               return -EINVAL;
+       next_flag:
+               f = strtok(NULL, "-");
+       }
+       return 0;
+}

diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h
index f1c405b76339e1d26710af330273808da78c7794..c7d62b8d40b219e72e3616c82a25fafe08f8455d 100644 (file)
--- a/lib/ext2fs/ext2_fs.h
+++ b/lib/ext2fs/ext2_fs.h
@@ -1127,4 +1127,11 @@ struct mmp_struct {
  */
 #define EXT4_INLINE_DATA_DOTDOT_SIZE   (4)
 
+#define EXT4_ENC_ASCII         0
+#define EXT4_ENC_UTF8_11_0     1
+
+#define EXT4_ENC_STRICT_MODE_FL                        (1 << 0) /* Reject invalid sequences */
+#define EXT4_UTF8_NORMALIZATION_TYPE_NFKD      (1 << 1)
+#define EXT4_UTF8_CASEFOLD_TYPE_NFKDCF         (1 << 4)
+
 #endif /* _LINUX_EXT2_FS_H */