Backport the apr_escape() interface to apr v1.5.

git-svn-id: https://svn.apache.org/repos/asf/apr/apr/branches/1.5.x@1530799 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 1150 insertions, 0 deletions

diff --git a/encoding/apr_escape.c b/encoding/apr_escape.c
new file mode 100644
index 000000000..8bb403c14
--- /dev/null
+++ b/encoding/apr_escape.c
@@ -0,0 +1,1150 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* escape/unescape functions.
+ *
+ * These functions perform various escaping operations, and are provided in
+ * pairs, a function to query the length of and escape existing buffers, as
+ * well as companion functions to perform the same process to memory
+ * allocated from a pool.
+ *
+ * The API is designed to have the smallest possible RAM footprint, and so
+ * will only allocate the exact amount of RAM needed for each conversion.
+ */
+
+#include "apr_escape.h"
+#include "apr_escape_test_char.h"
+#include "apr_lib.h"
+#include "apr_strings.h"
+
+/* helper for Latin1 <-> entity encoding */
+#if APR_CHARSET_EBCDIC
+#include "apr_xlate.h"
+#define RAW_ASCII_CHAR(ch)  apr_xlate_conv_byte(ap_hdrs_from_ascii, \
+                                                (unsigned char)ch)
+#else /* APR_CHARSET_EBCDIC */
+#define RAW_ASCII_CHAR(ch)  (ch)
+#endif /* !APR_CHARSET_EBCDIC */
+
+/* we assume the folks using this ensure 0 <= c < 256... which means
+ * you need a cast to (unsigned char) first, you can't just plug a
+ * char in here and get it to work, because if char is signed then it
+ * will first be sign extended.
+ */
+#define TEST_CHAR(c, f)        (test_char_table[(unsigned)(c)] & (f))
+
+APR_DECLARE(apr_status_t) apr_escape_shell(char *escaped, const char *str,
+        apr_ssize_t slen, apr_size_t *len)
+{
+    unsigned char *d;
+    const unsigned char *s;
+    apr_size_t size = 1;
+    int found = 0;
+
+    d = (unsigned char *) escaped;
+    s = (const unsigned char *) str;
+
+    if (s) {
+        if (d) {
+            for (; *s && slen; ++s, slen--) {
+#if defined(OS2) || defined(WIN32)
+                /*
+                 * Newlines to Win32/OS2 CreateProcess() are ill advised.
+                 * Convert them to spaces since they are effectively white
+                 * space to most applications
+                 */
+                if (*s == '\r' || *s == '\n') {
+                    if (d) {
+                        *d++ = ' ';
+                        found = 1;
+                    }
+                    continue;
+                }
+#endif
+                if (TEST_CHAR(*s, T_ESCAPE_SHELL_CMD)) {
+                    *d++ = '\\';
+                    size++;
+                    found = 1;
+                }
+                *d++ = *s;
+                size++;
+            }
+            *d = '\0';
+        }
+        else {
+            for (; *s && slen; ++s, slen--) {
+                if (TEST_CHAR(*s, T_ESCAPE_SHELL_CMD)) {
+                    size++;
+                    found = 1;
+                }
+                size++;
+            }
+        }
+    }
+
+    if (len) {
+        *len = size;
+    }
+    if (!found) {
+        return APR_NOTFOUND;
+    }
+
+    return APR_SUCCESS;
+}
+
+APR_DECLARE(const char *) apr_pescape_shell(apr_pool_t *p, const char *str)
+{
+    apr_size_t len;
+
+    switch (apr_escape_shell(NULL, str, APR_ESCAPE_STRING, &len)) {
+    case APR_SUCCESS: {
+        char *cmd = apr_palloc(p, len);
+        apr_escape_shell(cmd, str, APR_ESCAPE_STRING, NULL);
+        return cmd;
+    }
+    case APR_NOTFOUND: {
+        break;
+    }
+    }
+
+    return str;
+}
+
+static char x2c(const char *what)
+{
+    register char digit;
+
+#if !APR_CHARSET_EBCDIC
+    digit =
+            ((what[0] >= 'A') ? ((what[0] & 0xdf) - 'A') + 10 : (what[0] - '0'));
+    digit *= 16;
+    digit += (what[1] >= 'A' ? ((what[1] & 0xdf) - 'A') + 10 : (what[1] - '0'));
+#else /*APR_CHARSET_EBCDIC*/
+    char xstr[5];
+    xstr[0]='0';
+    xstr[1]='x';
+    xstr[2]=what[0];
+    xstr[3]=what[1];
+    xstr[4]='\0';
+    digit = apr_xlate_conv_byte(ap_hdrs_from_ascii,
+            0xFF & strtol(xstr, NULL, 16));
+#endif /*APR_CHARSET_EBCDIC*/
+    return (digit);
+}
+
+APR_DECLARE(apr_status_t) apr_unescape_url(char *escaped, const char *url,
+        apr_ssize_t slen, const char *forbid, const char *reserved, int plus,
+        apr_size_t *len)
+{
+    apr_size_t size = 1;
+    int found = 0;
+    const char *s = (const char *) url;
+    char *d = (char *) escaped;
+    register int badesc, badpath;
+
+    if (!url) {
+        return APR_NOTFOUND;
+    }
+
+    badesc = 0;
+    badpath = 0;
+    if (s) {
+        if (d) {
+            for (; *s && slen; ++s, d++, slen--) {
+                if (plus && *s == '+') {
+                    *d = ' ';
+                    found = 1;
+                }
+                else if (*s != '%') {
+                    *d = *s;
+                }
+                else {
+                    if (!apr_isxdigit(*(s + 1)) || !apr_isxdigit(*(s + 2))) {
+                        badesc = 1;
+                        *d = '%';
+                    }
+                    else {
+                        char decoded;
+                        decoded = x2c(s + 1);
+                        if ((decoded == '\0')
+                                || (forbid && strchr(forbid, decoded))) {
+                            badpath = 1;
+                            *d = decoded;
+                            s += 2;
+                            slen -= 2;
+                        }
+                        else if (reserved && strchr(reserved, decoded)) {
+                            *d++ = *s++;
+                            *d++ = *s++;
+                            *d = *s;
+                            size += 2;
+                        }
+                        else {
+                            *d = decoded;
+                            s += 2;
+                            slen -= 2;
+                            found = 1;
+                        }
+                    }
+                }
+                size++;
+            }
+            *d = '\0';
+        }
+        else {
+            for (; *s && slen; ++s, slen--) {
+                if (plus && *s == '+') {
+                    found = 1;
+                }
+                else if (*s != '%') {
+                    /* character unchanged */
+                }
+                else {
+                    if (!apr_isxdigit(*(s + 1)) || !apr_isxdigit(*(s + 2))) {
+                        badesc = 1;
+                    }
+                    else {
+                        char decoded;
+                        decoded = x2c(s + 1);
+                        if ((decoded == '\0')
+                                || (forbid && strchr(forbid, decoded))) {
+                            badpath = 1;
+                            s += 2;
+                            slen -= 2;
+                        }
+                        else if (reserved && strchr(reserved, decoded)) {
+                            s += 2;
+                            slen -= 2;
+                            size += 2;
+                        }
+                        else {
+                            s += 2;
+                            slen -= 2;
+                            found = 1;
+                        }
+                    }
+                }
+                size++;
+            }
+        }
+    }
+
+    if (len) {
+        *len = size;
+    }
+    if (badesc) {
+        return APR_EINVAL;
+    }
+    else if (badpath) {
+        return APR_BADCH;
+    }
+    else if (!found) {
+        return APR_NOTFOUND;
+    }
+
+    return APR_SUCCESS;
+}
+
+APR_DECLARE(const char *) apr_punescape_url(apr_pool_t *p, const char *url,
+        const char *forbid, const char *reserved, int plus)
+{
+    apr_size_t len;
+
+    switch (apr_unescape_url(NULL, url, APR_ESCAPE_STRING, forbid, reserved,
+            plus, &len)) {
+    case APR_SUCCESS: {
+        char *buf = apr_palloc(p, len);
+        apr_unescape_url(buf, url, APR_ESCAPE_STRING, forbid, reserved, plus,
+                NULL);
+        return buf;
+    }
+    case APR_EINVAL:
+    case APR_BADCH: {
+        return NULL;
+    }
+    case APR_NOTFOUND: {
+        break;
+    }
+    }
+
+    return url;
+}
+
+/* c2x takes an unsigned, and expects the caller has guaranteed that
+ * 0 <= what < 256... which usually means that you have to cast to
+ * unsigned char first, because (unsigned)(char)(x) first goes through
+ * signed extension to an int before the unsigned cast.
+ *
+ * The reason for this assumption is to assist gcc code generation --
+ * the unsigned char -> unsigned extension is already done earlier in
+ * both uses of this code, so there's no need to waste time doing it
+ * again.
+ */
+static const char c2x_table[] = "0123456789abcdef";
+
+static APR_INLINE unsigned char *c2x(unsigned what, unsigned char prefix,
+        unsigned char *where)
+{
+#if APR_CHARSET_EBCDIC
+    what = apr_xlate_conv_byte(ap_hdrs_to_ascii, (unsigned char)what);
+#endif /*APR_CHARSET_EBCDIC*/
+    *where++ = prefix;
+    *where++ = c2x_table[what >> 4];
+    *where++ = c2x_table[what & 0xf];
+    return where;
+}
+
+APR_DECLARE(apr_status_t) apr_escape_path_segment(char *escaped,
+        const char *str, apr_ssize_t slen, apr_size_t *len)
+{
+    apr_size_t size = 1;
+    int found = 0;
+    const unsigned char *s = (const unsigned char *) str;
+    unsigned char *d = (unsigned char *) escaped;
+    unsigned c;
+
+    if (s) {
+        if (d) {
+            while ((c = *s) && slen) {
+                if (TEST_CHAR(c, T_ESCAPE_PATH_SEGMENT)) {
+                    d = c2x(c, '%', d);
+                    size += 2;
+                    found = 1;
+                }
+                else {
+                    *d++ = c;
+                }
+                ++s;
+                size++;
+                slen--;
+            }
+            *d = '\0';
+        }
+        else {
+            while ((c = *s) && slen) {
+                if (TEST_CHAR(c, T_ESCAPE_PATH_SEGMENT)) {
+                    size += 2;
+                    found = 1;
+                }
+                ++s;
+                size++;
+                slen--;
+            }
+        }
+    }
+
+    if (len) {
+        *len = size;
+    }
+    if (!found) {
+        return APR_NOTFOUND;
+    }
+
+    return APR_SUCCESS;
+}
+
+APR_DECLARE(const char *) apr_pescape_path_segment(apr_pool_t *p,
+        const char *str)
+{
+    apr_size_t len;
+
+    switch (apr_escape_path_segment(NULL, str, APR_ESCAPE_STRING, &len)) {
+    case APR_SUCCESS: {
+        char *cmd = apr_palloc(p, len);
+        apr_escape_path_segment(cmd, str, APR_ESCAPE_STRING, NULL);
+        return cmd;
+    }
+    case APR_NOTFOUND: {
+        break;
+    }
+    }
+
+    return str;
+}
+
+APR_DECLARE(apr_status_t) apr_escape_path(char *escaped, const char *path,
+        apr_ssize_t slen, int partial, apr_size_t *len)
+{
+    apr_size_t size = 1;
+    int found = 0;
+    const unsigned char *s = (const unsigned char *) path;
+    unsigned char *d = (unsigned char *) escaped;
+    unsigned c;
+
+    if (!path) {
+        return APR_NOTFOUND;
+    }
+
+    if (!partial) {
+        const char *colon = strchr(path, ':');
+        const char *slash = strchr(path, '/');
+
+        if (colon && (!slash || colon < slash)) {
+            if (d) {
+                *d++ = '.';
+                *d++ = '/';
+            }
+            size += 2;
+            found = 1;
+        }
+    }
+    if (d) {
+        while ((c = *s) && slen) {
+            if (TEST_CHAR(c, T_OS_ESCAPE_PATH)) {
+                d = c2x(c, '%', d);
+            }
+            else {
+                *d++ = c;
+            }
+            ++s;
+            size++;
+            slen--;
+        }
+        *d = '\0';
+    }
+    else {
+        while ((c = *s) && slen) {
+            if (TEST_CHAR(c, T_OS_ESCAPE_PATH)) {
+                size += 2;
+                found = 1;
+            }
+            ++s;
+            size++;
+            slen--;
+        }
+    }
+
+    if (len) {
+        *len = size;
+    }
+    if (!found) {
+        return APR_NOTFOUND;
+    }
+
+    return APR_SUCCESS;
+}
+
+APR_DECLARE(const char *) apr_pescape_path(apr_pool_t *p, const char *str,
+        int partial)
+{
+    apr_size_t len;
+
+    switch (apr_escape_path(NULL, str, APR_ESCAPE_STRING, partial, &len)) {
+    case APR_SUCCESS: {
+        char *path = apr_palloc(p, len);
+        apr_escape_path(path, str, APR_ESCAPE_STRING, partial, NULL);
+        return path;
+    }
+    case APR_NOTFOUND: {
+        break;
+    }
+    }
+
+    return str;
+}
+
+APR_DECLARE(apr_status_t) apr_escape_urlencoded(char *escaped, const char *str,
+        apr_ssize_t slen, apr_size_t *len)
+{
+    apr_size_t size = 1;
+    int found = 0;
+    const unsigned char *s = (const unsigned char *) str;
+    unsigned char *d = (unsigned char *) escaped;
+    unsigned c;
+
+    if (s) {
+        if (d) {
+            while ((c = *s) && slen) {
+                if (TEST_CHAR(c, T_ESCAPE_URLENCODED)) {
+                    d = c2x(c, '%', d);
+                    size += 2;
+                    found = 1;
+                }
+                else if (c == ' ') {
+                    *d++ = '+';
+                    found = 1;
+                }
+                else {
+                    *d++ = c;
+                }
+                ++s;
+                size++;
+                slen--;
+            }
+            *d = '\0';
+        }
+        else {
+            while ((c = *s) && slen) {
+                if (TEST_CHAR(c, T_ESCAPE_URLENCODED)) {
+                    size += 2;
+                    found = 1;
+                }
+                else if (c == ' ') {
+                    found = 1;
+                }
+                ++s;
+                size++;
+                slen--;
+            }
+        }
+    }
+
+    if (len) {
+        *len = size;
+    }
+    if (!found) {
+        return APR_NOTFOUND;
+    }
+
+    return APR_SUCCESS;
+}
+
+APR_DECLARE(const char *) apr_pescape_urlencoded(apr_pool_t *p, const char *str)
+{
+    apr_size_t len;
+
+    switch (apr_escape_urlencoded(NULL, str, APR_ESCAPE_STRING, &len)) {
+    case APR_SUCCESS: {
+        char *encoded = apr_palloc(p, len);
+        apr_escape_urlencoded(encoded, str, APR_ESCAPE_STRING, NULL);
+        return encoded;
+    }
+    case APR_NOTFOUND: {
+        break;
+    }
+    }
+
+    return str;
+}
+
+APR_DECLARE(apr_status_t) apr_escape_entity(char *escaped, const char *str,
+        apr_ssize_t slen, int toasc, apr_size_t *len)
+{
+    apr_size_t size = 1;
+    int found = 0;
+    const unsigned char *s = (const unsigned char *) str;
+    unsigned char *d = (unsigned char *) escaped;
+    unsigned c;
+
+    if (s) {
+        if (d) {
+            while ((c = *s) && slen) {
+                if (TEST_CHAR(c, T_ESCAPE_XML)) {
+                    switch (c) {
+                    case '>': {
+                        memcpy(d, "&gt;", 4);
+                        size += 4;
+                        d += 4;
+                        break;
+                    }
+                    case '<': {
+                        memcpy(d, "&lt;", 4);
+                        size += 4;
+                        d += 4;
+                        break;
+                    }
+                    case '&': {
+                        memcpy(d, "&amp;", 5);
+                        size += 5;
+                        d += 5;
+                        break;
+                    }
+                    case '\"': {
+                        memcpy(d, "&quot;", 6);
+                        size += 6;
+                        d += 6;
+                        break;
+                    }
+                    case '\'': {
+                        memcpy(d, "&apos;", 6);
+                        size += 6;
+                        d += 6;
+                        break;
+                    }
+                    }
+                    found = 1;
+                }
+                else if (toasc && !apr_isascii(c)) {
+                    int offset = apr_snprintf((char *) d, 6, "&#%3.3d;", c);
+                    size += offset;
+                    d += offset;
+                    found = 1;
+                }
+                else {
+                    *d++ = c;
+                    size++;
+                }
+                ++s;
+                slen--;
+            }
+            *d = '\0';
+        }
+        else {
+            while ((c = *s) && slen) {
+                if (TEST_CHAR(c, T_ESCAPE_XML)) {
+                    switch (c) {
+                    case '>': {
+                        size += 4;
+                        break;
+                    }
+                    case '<': {
+                        size += 4;
+                        break;
+                    }
+                    case '&': {
+                        size += 5;
+                        break;
+                    }
+                    case '\"': {
+                        size += 6;
+                        break;
+                    }
+                    case '\'': {
+                        size += 6;
+                        break;
+                    }
+                    }
+                    found = 1;
+                }
+                else if (toasc && !apr_isascii(c)) {
+                    char buf[8];
+                    size += apr_snprintf(buf, 6, "&#%3.3d;", c);
+                    found = 1;
+                }
+                else {
+                    size++;
+                }
+                ++s;
+                slen--;
+            }
+        }
+    }
+
+    if (len) {
+        *len = size;
+    }
+    if (!found) {
+        return APR_NOTFOUND;
+    }
+
+    return APR_SUCCESS;
+}
+
+APR_DECLARE(const char *) apr_pescape_entity(apr_pool_t *p, const char *str,
+        int toasc)
+{
+    apr_size_t len;
+
+    switch (apr_escape_entity(NULL, str, APR_ESCAPE_STRING, toasc, &len)) {
+    case APR_SUCCESS: {
+        char *cmd = apr_palloc(p, len);
+        apr_escape_entity(cmd, str, APR_ESCAPE_STRING, toasc, NULL);
+        return cmd;
+    }
+    case APR_NOTFOUND: {
+        break;
+    }
+    }
+
+    return str;
+}
+
+/* maximum length of any ISO-LATIN-1 HTML entity name. */
+#define MAXENTLEN (6)
+
+APR_DECLARE(apr_status_t) apr_unescape_entity(char *unescaped, const char *str,
+        apr_ssize_t slen, apr_size_t *len)
+{
+    int found = 0;
+    apr_size_t size = 1;
+    int val, i, j;
+    char *d = unescaped;
+    const char *s = str;
+    const char *ents;
+    static const char * const entlist[MAXENTLEN + 1] =
+    {
+            NULL, /* 0 */
+            NULL, /* 1 */
+            "lt\074gt\076", /* 2 */
+            "amp\046ETH\320eth\360", /* 3 */
+            "quot\042Auml\304Euml\313Iuml\317Ouml\326Uuml\334auml\344euml"
+            "\353iuml\357ouml\366uuml\374yuml\377", /* 4 */
+            "Acirc\302Aring\305AElig\306Ecirc\312Icirc\316Ocirc\324Ucirc"
+            "\333THORN\336szlig\337acirc\342aring\345aelig\346ecirc\352"
+            "icirc\356ocirc\364ucirc\373thorn\376", /* 5 */
+            "Agrave\300Aacute\301Atilde\303Ccedil\307Egrave\310Eacute\311"
+            "Igrave\314Iacute\315Ntilde\321Ograve\322Oacute\323Otilde"
+            "\325Oslash\330Ugrave\331Uacute\332Yacute\335agrave\340"
+            "aacute\341atilde\343ccedil\347egrave\350eacute\351igrave"
+            "\354iacute\355ntilde\361ograve\362oacute\363otilde\365"
+            "oslash\370ugrave\371uacute\372yacute\375" /* 6 */
+    };
+
+    if (s) {
+        if (d) {
+            for (; *s != '\0' && slen; s++, d++, size++, slen--) {
+                if (*s != '&') {
+                    *d = *s;
+                    continue;
+                }
+                /* find end of entity */
+                for (i = 1; s[i] != ';' && s[i] != '\0' && (slen - i) != 0;
+                        i++) {
+                    continue;
+                }
+
+                if (s[i] == '\0' || (slen - i) == 0) { /* treat as normal data */
+                    *d = *s;
+                    continue;
+                }
+
+                /* is it numeric ? */
+                if (s[1] == '#') {
+                    for (j = 2, val = 0; j < i && apr_isdigit(s[j]); j++) {
+                        val = val * 10 + s[j] - '0';
+                    }
+                    s += i;
+                    if (j < i || val <= 8 || (val >= 11 && val <= 31)
+                            || (val >= 127 && val <= 160) || val >= 256) {
+                        d--; /* no data to output */
+                        size--;
+                    }
+                    else {
+                        *d = RAW_ASCII_CHAR(val);
+                        found = 1;
+                    }
+                }
+                else {
+                    j = i - 1;
+                    if (j > MAXENTLEN || entlist[j] == NULL) {
+                        /* wrong length */
+                        *d = '&';
+                        continue; /* skip it */
+                    }
+                    for (ents = entlist[j]; *ents != '\0'; ents += i) {
+                        if (strncmp(s + 1, ents, j) == 0) {
+                            break;
+                        }
+                    }
+
+                    if (*ents == '\0') {
+                        *d = '&'; /* unknown */
+                    }
+                    else {
+                        *d = RAW_ASCII_CHAR(((const unsigned char *) ents)[j]);
+                        s += i;
+                        slen -= i;
+                        found = 1;
+                    }
+                }
+            }
+            *d = '\0';
+        }
+        else {
+            for (; *s != '\0' && slen; s++, size++, slen--) {
+                if (*s != '&') {
+                    continue;
+                }
+                /* find end of entity */
+                for (i = 1; s[i] != ';' && s[i] != '\0' && (slen - i) != 0;
+                        i++) {
+                    continue;
+                }
+
+                if (s[i] == '\0' || (slen - i) == 0) { /* treat as normal data */
+                    continue;
+                }
+
+                /* is it numeric ? */
+                if (s[1] == '#') {
+                    for (j = 2, val = 0; j < i && apr_isdigit(s[j]); j++) {
+                        val = val * 10 + s[j] - '0';
+                    }
+                    s += i;
+                    if (j < i || val <= 8 || (val >= 11 && val <= 31)
+                            || (val >= 127 && val <= 160) || val >= 256) {
+                        /* no data to output */
+                        size--;
+                    }
+                    else {
+                        found = 1;
+                    }
+                }
+                else {
+                    j = i - 1;
+                    if (j > MAXENTLEN || entlist[j] == NULL) {
+                        /* wrong length */
+                        continue; /* skip it */
+                    }
+                    for (ents = entlist[j]; *ents != '\0'; ents += i) {
+                        if (strncmp(s + 1, ents, j) == 0) {
+                            break;
+                        }
+                    }
+
+                    if (*ents == '\0') {
+                        /* unknown */
+                    }
+                    else {
+                        s += i;
+                        slen -= i;
+                        found = 1;
+                    }
+                }
+            }
+        }
+    }
+
+    if (len) {
+        *len = size;
+    }
+    if (!found) {
+        return APR_NOTFOUND;
+    }
+
+    return APR_SUCCESS;
+}
+
+APR_DECLARE(const char *) apr_punescape_entity(apr_pool_t *p, const char *str)
+{
+    apr_size_t len;
+
+    switch (apr_unescape_entity(NULL, str, APR_ESCAPE_STRING, &len)) {
+    case APR_SUCCESS: {
+        char *cmd = apr_palloc(p, len);
+        apr_unescape_entity(cmd, str, APR_ESCAPE_STRING, NULL);
+        return cmd;
+    }
+    case APR_NOTFOUND: {
+        break;
+    }
+    }
+
+    return str;
+}
+
+APR_DECLARE(apr_status_t) apr_escape_echo(char *escaped, const char *str,
+        apr_ssize_t slen, int quote, apr_size_t *len)
+{
+    apr_size_t size = 1;
+    int found = 0;
+    const unsigned char *s = (const unsigned char *) str;
+    unsigned char *d = (unsigned char *) escaped;
+    unsigned c;
+
+    if (s) {
+        if (d) {
+            while ((c = *s) && slen) {
+                if (TEST_CHAR(c, T_ESCAPE_ECHO)) {
+                    *d++ = '\\';
+                    size++;
+                    switch (c) {
+                    case '\a':
+                        *d++ = 'a';
+                        size++;
+                        found = 1;
+                        break;
+                    case '\b':
+                        *d++ = 'b';
+                        size++;
+                        found = 1;
+                        break;
+                    case '\f':
+                        *d++ = 'f';
+                        size++;
+                        found = 1;
+                        break;
+                    case '\n':
+                        *d++ = 'n';
+                        size++;
+                        found = 1;
+                        break;
+                    case '\r':
+                        *d++ = 'r';
+                        size++;
+                        found = 1;
+                        break;
+                    case '\t':
+                        *d++ = 't';
+                        size++;
+                        found = 1;
+                        break;
+                    case '\v':
+                        *d++ = 'v';
+                        size++;
+                        found = 1;
+                        break;
+                    case '\\':
+                        *d++ = '\\';
+                        size++;
+                        found = 1;
+                        break;
+                    case '"':
+                        if (quote) {
+                            *d++ = c;
+                            size++;
+                            found = 1;
+                        }
+                        else {
+                            d[-1] = c;
+                        }
+                        break;
+                    default:
+                        c2x(c, 'x', d);
+                        d += 3;
+                        size += 3;
+                        found = 1;
+                        break;
+                    }
+                }
+                else {
+                    *d++ = c;
+                    size++;
+                }
+                ++s;
+                slen--;
+            }
+            *d = '\0';
+        }
+        else {
+            while ((c = *s) && slen) {
+                if (TEST_CHAR(c, T_ESCAPE_ECHO)) {
+                    size++;
+                    switch (c) {
+                    case '\a':
+                    case '\b':
+                    case '\f':
+                    case '\n':
+                    case '\r':
+                    case '\t':
+                    case '\v':
+                    case '\\':
+                        size++;
+                        found = 1;
+                        break;
+                    case '"':
+                        if (quote) {
+                            size++;
+                            found = 1;
+                        }
+                        break;
+                    default:
+                        size += 3;
+                        found = 1;
+                        break;
+                    }
+                }
+                else {
+                    size++;
+                }
+                ++s;
+                slen--;
+            }
+        }
+    }
+
+    if (len) {
+        *len = size;
+    }
+    if (!found) {
+        return APR_NOTFOUND;
+    }
+
+    return APR_SUCCESS;
+}
+
+APR_DECLARE(const char *) apr_pescape_echo(apr_pool_t *p, const char *str,
+        int quote)
+{
+    apr_size_t len;
+
+    switch (apr_escape_echo(NULL, str, APR_ESCAPE_STRING, quote, &len)) {
+    case APR_SUCCESS: {
+        char *cmd = apr_palloc(p, len);
+        apr_escape_echo(cmd, str, APR_ESCAPE_STRING, quote, NULL);
+        return cmd;
+    }
+    case APR_NOTFOUND: {
+        break;
+    }
+    }
+
+    return str;
+}
+
+APR_DECLARE(apr_status_t) apr_escape_hex(char *dest, const void *src,
+        apr_size_t srclen, int colon, apr_size_t *len)
+{
+    const unsigned char *in = src;
+    apr_size_t size;
+
+    if (!src) {
+        return APR_NOTFOUND;
+    }
+
+    if (dest) {
+        for (size = 0; size < srclen; size++) {
+            if (colon && size) {
+                *dest++ = ':';
+            }
+            *dest++ = c2x_table[in[size] >> 4];
+            *dest++ = c2x_table[in[size] & 0xf];
+        }
+        *dest = '\0';
+    }
+
+    if (len) {
+        if (colon && srclen) {
+            *len = srclen * 3;
+        }
+        else {
+            *len = srclen * 2 + 1;
+        }
+    }
+
+    return APR_SUCCESS;
+}
+
+APR_DECLARE(const char *) apr_pescape_hex(apr_pool_t *p, const void *src,
+        apr_size_t srclen, int colon)
+{
+    apr_size_t len;
+
+    switch (apr_escape_hex(NULL, src, srclen, colon, &len)) {
+    case APR_SUCCESS: {
+        char *cmd = apr_palloc(p, len);
+        apr_escape_hex(cmd, src, srclen, colon, NULL);
+        return cmd;
+    }
+    case APR_NOTFOUND: {
+        break;
+    }
+    }
+
+    return src;
+}
+
+APR_DECLARE(apr_status_t) apr_unescape_hex(void *dest, const char *str,
+        apr_ssize_t slen, int colon, apr_size_t *len)
+{
+    apr_size_t size = 0;
+    int flip = 0;
+    const unsigned char *s = (const unsigned char *) str;
+    unsigned char *d = (unsigned char *) dest;
+    unsigned c;
+    unsigned char u = 0;
+
+    if (s) {
+        if (d) {
+            while ((c = *s) && slen) {
+
+                if (!flip) {
+                    u = 0;
+                }
+
+                if (colon && c == ':' && !flip) {
+                    ++s;
+                    slen--;
+                    continue;
+                }
+                else if (apr_isdigit(c)) {
+                    u |= c - '0';
+                }
+                else if (apr_isupper(c) && c <= 'F') {
+                    u |= c - ('A' - 10);
+                }
+                else if (apr_islower(c) && c <= 'f') {
+                    u |= c - ('a' - 10);
+                }
+                else {
+                    return APR_BADCH;
+                }
+
+                if (flip) {
+                    *d++ = u;
+                    size++;
+                }
+                else {
+                    u <<= 4;
+                    *d = u;
+                }
+                flip = !flip;
+
+                ++s;
+                slen--;
+            }
+        }
+        else {
+            while ((c = *s) && slen) {
+
+                if (colon && c == ':' && !flip) {
+                    ++s;
+                    slen--;
+                    continue;
+                }
+                else if (apr_isdigit(c)) {
+                    /* valid */
+                }
+                else if (apr_isupper(c) && c <= 'F') {
+                    /* valid */
+                }
+                else if (apr_islower(c) && c <= 'f') {
+                    /* valid */
+                }
+                else {
+                    return APR_BADCH;
+                }
+
+                if (flip) {
+                    size++;
+                }
+                flip = !flip;
+
+                ++s;
+                slen--;
+            }
+        }
+    }
+
+    if (len) {
+        *len = size;
+    }
+    if (!s) {
+        return APR_NOTFOUND;
+    }
+
+    return APR_SUCCESS;
+}
+
+APR_DECLARE(const void *) apr_punescape_hex(apr_pool_t *p, const char *str,
+        int colon, apr_size_t *len)
+{
+    apr_size_t size;
+
+    switch (apr_unescape_hex(NULL, str, APR_ESCAPE_STRING, colon, &size)) {
+    case APR_SUCCESS: {
+        void *cmd = apr_palloc(p, size);
+        apr_unescape_hex(cmd, str, APR_ESCAPE_STRING, colon, len);
+        return cmd;
+    }
+    case APR_BADCH:
+    case APR_NOTFOUND: {
+        break;
+    }
+    }
+
+    return NULL;
+}