util: move all to shared/ and split external dependencies in separate internal libraries

Before:
  $ ldd /lib/systemd/systemd-timestamp
  linux-vdso.so.1 =>  (0x00007fffb05ff000)
  libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f90aac57000)
  libcap.so.2 => /lib64/libcap.so.2 (0x00007f90aaa53000)
  librt.so.1 => /lib64/librt.so.1 (0x00007f90aa84a000)
  libc.so.6 => /lib64/libc.so.6 (0x00007f90aa494000)
  /lib64/ld-linux-x86-64.so.2 (0x00007f90aae90000)
  libdl.so.2 => /lib64/libdl.so.2 (0x00007f90aa290000)
  libattr.so.1 => /lib64/libattr.so.1 (0x00007f90aa08a000)
  libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f90a9e6e000)

After:
  $ ldd systemd-timestamp
  linux-vdso.so.1 =>  (0x00007fff3cbff000)
  libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f5eaa1c3000)
  librt.so.1 => /lib64/librt.so.1 (0x00007f5ea9fbb000)
  libc.so.6 => /lib64/libc.so.6 (0x00007f5ea9c04000)
  /lib64/ld-linux-x86-64.so.2 (0x00007f5eaa3fc000)
  libdl.so.2 => /lib64/libdl.so.2 (0x00007f5ea9a00000)
  libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f5ea97e4000)

1 files changed, 214 insertions, 0 deletions

diff --git a/src/shared/utf8.c b/src/shared/utf8.c
new file mode 100644
index 0000000000..11619dce2f
--- /dev/null
+++ b/src/shared/utf8.c
@@ -0,0 +1,214 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2012 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+/* This file is based on the GLIB utf8 validation functions. The
+ * original license text follows. */
+
+/* gutf8.c - Operations on UTF-8 strings.
+ *
+ * Copyright (C) 1999 Tom Tromey
+ * Copyright (C) 2000 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.         See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <inttypes.h>
+#include <string.h>
+#include <stdbool.h>
+
+#include "utf8.h"
+
+#define FILTER_CHAR '_'
+
+static inline bool is_unicode_valid(uint32_t ch) {
+
+        if (ch >= 0x110000) /* End of unicode space */
+                return false;
+        if ((ch & 0xFFFFF800) == 0xD800) /* Reserved area for UTF-16 */
+                return false;
+        if ((ch >= 0xFDD0) && (ch <= 0xFDEF)) /* Reserved */
+                return false;
+        if ((ch & 0xFFFE) == 0xFFFE) /* BOM (Byte Order Mark) */
+                return false;
+
+        return true;
+}
+
+static inline bool is_continuation_char(uint8_t ch) {
+        if ((ch & 0xc0) != 0x80) /* 10xxxxxx */
+                return false;
+        return true;
+}
+
+static inline void merge_continuation_char(uint32_t *u_ch, uint8_t ch) {
+        *u_ch <<= 6;
+        *u_ch |= ch & 0x3f;
+}
+
+static char* utf8_validate(const char *str, char *output) {
+        uint32_t val = 0;
+        uint32_t min = 0;
+        const uint8_t *p, *last;
+        int size;
+        uint8_t *o;
+
+        assert(str);
+
+        o = (uint8_t*) output;
+        for (p = (const uint8_t*) str; *p; p++) {
+                if (*p < 128) {
+                        if (o)
+                                *o = *p;
+                } else {
+                        last = p;
+
+                        if ((*p & 0xe0) == 0xc0) { /* 110xxxxx two-char seq. */
+                                size = 2;
+                                min = 128;
+                                val = (uint32_t) (*p & 0x1e);
+                                goto ONE_REMAINING;
+                        } else if ((*p & 0xf0) == 0xe0) { /* 1110xxxx three-char seq.*/
+                                size = 3;
+                                min = (1 << 11);
+                                val = (uint32_t) (*p & 0x0f);
+                                goto TWO_REMAINING;
+                        } else if ((*p & 0xf8) == 0xf0) { /* 11110xxx four-char seq */
+                                size = 4;
+                                min = (1 << 16);
+                                val = (uint32_t) (*p & 0x07);
+                        } else
+                                goto error;
+
+                        p++;
+                        if (!is_continuation_char(*p))
+                                goto error;
+                        merge_continuation_char(&val, *p);
+
+                TWO_REMAINING:
+                        p++;
+                        if (!is_continuation_char(*p))
+                                goto error;
+                        merge_continuation_char(&val, *p);
+
+                ONE_REMAINING:
+                        p++;
+                        if (!is_continuation_char(*p))
+                                goto error;
+                        merge_continuation_char(&val, *p);
+
+                        if (val < min)
+                                goto error;
+
+                        if (!is_unicode_valid(val))
+                                goto error;
+
+                        if (o) {
+                                memcpy(o, last, (size_t) size);
+                                o += size;
+                        }
+
+                        continue;
+
+                error:
+                        if (o) {
+                                *o = FILTER_CHAR;
+                                p = last; /* We retry at the next character */
+                        } else
+                                goto failure;
+                }
+
+                if (o)
+                        o++;
+        }
+
+        if (o) {
+                *o = '\0';
+                return output;
+        }
+
+        return (char*) str;
+
+failure:
+        return NULL;
+}
+
+char* utf8_is_valid (const char *str) {
+        return utf8_validate(str, NULL);
+}
+
+char* utf8_filter (const char *str) {
+        char *new_str;
+
+        assert(str);
+
+        new_str = malloc(strlen(str) + 1);
+        if (!new_str)
+                return NULL;
+
+        return utf8_validate(str, new_str);
+}
+
+char *ascii_is_valid(const char *str) {
+        const char *p;
+
+        assert(str);
+
+        for (p = str; *p; p++)
+                if ((unsigned char) *p >= 128)
+                        return NULL;
+
+        return (char*) str;
+}
+
+char *ascii_filter(const char *str) {
+        char *r, *s, *d;
+        size_t l;
+
+        assert(str);
+
+        l = strlen(str);
+        r = malloc(l + 1);
+        if (!r)
+                return NULL;
+
+        for (s = r, d = r; *s; s++)
+                if ((unsigned char) *s < 128)
+                        *(d++) = *s;
+
+        *d = 0;
+
+        return r;
+}