[FIX] BMP for MUC nicks, dip toes in vCard avatars

Can, your, Bifrost, Do, That. -lh

README.MD

@@ -1,22 +1,25 @@
 # Parsee - the jealous XMPP<=>Matrix bridge
 Parsee is a Matrix<=>XMPP bridge written in C99, with Cytoplasm, similar to Bifrost, but it is 
 NOT a drop-in replacment.
-Currently, it is *alpha* stage, which means that I wouldn't recommend using this in production, as I can change anything, at any time.
+Currently, it is *alpha* stage, which means that I wouldn't recommend using this in production, 
+as I can change anything, at any time, and it may behave strangely at times.
 
 ## Why?
 ### Naming
 The name 'Parsee' is actually a reference to [Parsee Mizuhashi](https://en.touhouwiki.net/wiki/Parsee_Mizuhashi), 
-a "*bridge* princess".
+a "*bridge* princess". The other name you actually can sometimes see explains itself, so I won't 
+be talking about it.
 
 ### Reasoning (personal to LDA)
 I hate Bifrost. I also wanted to dip my toes in XMPP, XML, and bridges a bit. Also, as a sister 
 project to KappaChat, this means that I can integrate Parsee with KappaChat however I wish it 
 to be, which allows me to mess around with a codebase I'm already familiar with.
-A more "up-to-date" reason may be to have a small, 'Just Werks' bridging solution *that is good*.
+A more "up-to-date" reason may be to have a small, 'Just Werks' bridging solution *that is good*, 
+and maybe as a testing ground for Cytoplasm features I sometimes add.
 
-Well, I'm *trying* to do that, at least. 
+(Well, I'm *trying* to do that, at least. 
 Please scream at me if that fails(or just doesn't run on a overclocked Raspberry 
-Pi 4B, which, by the way, is literally where Parsee+XMPP is running for now.)
+Pi 4B, which, by the way, is literally where Parsee+XMPP is running for now.))
 
 ### "Why not just use Matrix lol"
 ### "Why not just use XMPP lol"
@@ -26,7 +29,7 @@ a bridge may be a good way to start.
 
 ## BUILDING
 ```sh
-$ cc configure.c -o configure
+$ cc configure.c -o configure # that or use tcc -run to consolidate these two steps.
 $ ./configure # use -s if you want static Parsee+MbedTLS, use -s -l if LMDB is needed
 $ make
 $ make [PREFIX=...] install # run as root if on a protected dir like /usr
@@ -65,17 +68,21 @@ returns with a landing page, then this side works. You can read it for some more
 
 ## DOCS
 Currently, the main sources of documentation are the Ayadocs(for headers) and the manpages
-(see `etc/man`)
+(see `etc/man`).
 
 ## TODOS before 1.0 rolls around
-- PROPER FUCKING AVATARS
+- Make Parsee go *vroooooooooommmmmmm*, by NOT asking the server constantly 
+about what is available and what is not, as that is a source of latency, and 
+thus slowdowns.
+- PROPER FUCKING VCARD AVATARS
     XMPP->Matrix is decent, Matrix->XMPP is effectively a WIP
 - Add [libomemo](https://github.com/gkdr/libomemo) or something as an optional dependency. 
     - It depends on more stuff anyways, and I don't want to weigh down the 
     dependency list of Parsee for that.
     - Matrix's libolm is deprecated. They replaced it with a Rust version that 
     pulls in *way too many* dependencies, and that lacks a C binding. We may 
-    put in the work of either forking off libolm or making a binding to KappaChat.
+    ~~put in the work of either forking off libolm or~~ be making a binding with 
+    KappaChat(when I get around to remaking UI :p).
         - Josh did infact tell me that maybe C bindings may happen. I'd be 
         willing to help out, but IDK. In any case, this will at best be an 
         extension packagers may integrate properly.

src/Main.c

@@ -12,6 +12,7 @@
 #include <signal.h>
 #include <stdlib.h>
 
+#include <Unistring.h>
 #include <Parsee.h>
 #include <XMPP.h>
 #include <AS.h>
@@ -71,6 +72,18 @@ Main(Array *args, HashMap *env)
 
     start = UtilTsMillis();
 
+    {
+        Unistr *s = UnistrCreate("Array 日本語🌋");
+        size_t i;
+        for (i = 0; i < UnistrSize(s); i++)
+        {
+            uint32_t cp = UnistrGetch(s, i);
+            Log(LOG_INFO, "%X", cp);
+        }
+
+        UnistrFree(s);
+    }
+
     memset(&conf, 0, sizeof(conf));
     Log(LOG_INFO, 
         "%s - v%s[%s] (Cytoplasm %s)", 

src/MatrixEventHandler.c

@@ -8,6 +8,7 @@
 #include <stdlib.h>
 
 #include <StanzaBuilder.h>
+#include <Unistring.h>
 #include <Matrix.h>
 #include <AS.h>
 
@@ -21,10 +22,17 @@ JoinMUC(ParseeData *data, HashMap *event, char *jid, char *muc, char *name)
 {
     char *sender = GrabString(event, 1, "sender");
 
-    char *nick = StrDuplicate(name);
+    Unistr *uninick = UnistrCreate(name);
+    Unistr *filtered = UnistrFilter(uninick, UnistrIsBMP);
+    char *nick = UnistrC(filtered);
     char *rev = StrConcat(3, muc, "/", nick);
     int nonce = 0;
 
+    Log(LOG_DEBUG, "MUCJOINER: filtered '%s' to '%s'", name, nick);
+
+    UnistrFree(uninick);
+    UnistrFree(filtered);
+
     while (!XMPPJoinMUC(data->jabber, jid, rev, true) && nonce < 32)
     {
         char *nonce_str = StrInt(nonce);

src/Unistr.c

@@ -0,0 +1,225 @@
+#include <Unistring.h>
+
+#include <Cytoplasm/Memory.h>
+#include <Cytoplasm/Str.h>
+#include <Cytoplasm/Log.h>
+
+#include <string.h>
+
+struct Unistr {
+    size_t length;
+    uint32_t *codepoints;
+};
+
+void 
+UnistrAddch(Unistr *unistr, uint32_t u)
+{
+    if (!unistr || !u)
+    {
+        return;
+    }
+    unistr->length++;
+    unistr->codepoints = Realloc(
+        unistr->codepoints, 
+        unistr->length * sizeof(*unistr->codepoints)
+    );
+
+    unistr->codepoints[unistr->length - 1] = u;
+}
+
+static bool
+UTFIsN(char *off, size_t available, int n, uint8_t pc)
+{
+    int i;
+    uint8_t *offu = (uint8_t *) off;
+    if ((available < n) || ((*offu >> (8-n-1)) != pc))
+    {
+        return false;
+    }
+
+    for (i = 0; i < n - 1; i++)
+    {
+        if ((offu[i+1] >> 6) != 0b10)
+        {
+            return false;
+        }
+    }
+    return true;
+}
+
+Unistr *
+UnistrCreate(char *src)
+{
+    size_t len, i;
+    Unistr *str;
+    char *start;
+    if (!src)
+    {
+        return NULL;
+    }
+
+    len = strlen(src);
+    str = Malloc(sizeof(*str));
+    str->length = 0;
+    str->codepoints = NULL;
+
+    /* We can't just set the length to {len}. */
+    for (i = 0; i < len; i++)
+    {
+        char byte = src[i];
+        size_t available = len - i;
+        if ((byte & 0x80) == 0)
+        {
+            /* This is a regular codepoint */
+            UnistrAddch(str, byte & 0x7F);
+            continue;
+        }
+        else if (UTFIsN(&src[i], available, 2, 0b110))
+        {
+            char a = src[i+0] & 0b00011111;
+            char b = src[i+1] & 0b00111111;
+            uint32_t u = (a << (6 * 1)) | b;
+
+            /* Overlongs are errors. */
+            if (u < 0x0080 || u > 0x07FF)
+            {
+                UnistrFree(str);
+                return NULL;
+            }
+
+            UnistrAddch(str, u);
+            i += 2 - 1;
+            continue;
+        }
+        else if (UTFIsN(&src[i], available, 3, 0b1110))
+        {
+            char a = src[i+0] & 0b00001111;
+            char b = src[i+1] & 0b00111111;
+            char c = src[i+2] & 0b00111111;
+            uint32_t u = 
+                (a << (6 * 2)) | 
+                (b << (6 * 1)) | 
+                (c << (6 * 0)) ;
+
+            /* Overlongs are errors. */
+            if (u < 0x0800 || u > 0xFFFF)
+            {
+                UnistrFree(str);
+                return NULL;
+            }
+
+            UnistrAddch(str, u);
+            i += 3 - 1;
+            continue;
+        }
+        else if (UTFIsN(&src[i], available, 4, 0b11110))
+        {
+            char a = src[i+0] & 0b00000111;
+            char b = src[i+1] & 0b00111111;
+            char c = src[i+2] & 0b00111111;
+            char d = src[i+3] & 0b00111111;
+            uint32_t u = 
+                (a << (6 * 3)) | 
+                (b << (6 * 2)) | 
+                (c << (6 * 1)) |
+                (d << (6 * 0)) ;
+
+            /* Overlongs are errors. */
+            if (u < 0x10000 || u > 0x10FFFF)
+            {
+                UnistrFree(str);
+                return NULL;
+            }
+
+            UnistrAddch(str, u);
+            i += 4 - 1;
+            continue;
+            
+        }
+    }
+
+    return str;
+}
+void 
+UnistrFree(Unistr *unistr)
+{
+    if (!unistr)
+    {
+        return;
+    }
+
+    Free(unistr->codepoints);
+    Free(unistr);
+}
+char * 
+UnistrC(Unistr *unistr)
+{
+    char *ret, *tmp, *utf;
+    size_t i;
+    if (!unistr)
+    {
+        return NULL;
+    }
+
+    ret = NULL;
+    for (i = 0; i < unistr->length; i++)
+    {
+        uint32_t code = unistr->codepoints[i];
+        utf = StrUtf8Encode(code);
+
+        tmp = ret;
+        ret = StrConcat(2, ret, utf);
+        Free(tmp);
+        Free(utf);
+    }
+
+    return ret;
+}
+size_t
+UnistrSize(Unistr *unistr)
+{
+    return unistr ? unistr->length : 0;
+}
+uint32_t 
+UnistrGetch(Unistr *unistr, size_t i)
+{
+    if (!unistr)
+    {
+        return 0;
+    }
+
+    return i < unistr->length ? unistr->codepoints[i] : 0;
+}
+bool
+UnistrIsBMP(uint32_t u)
+{
+    if (u == 0)
+    {
+        return NULL;
+    }
+
+    return u <= 0xFFFF;
+}
+Unistr *
+UnistrFilter(Unistr *str, UnistrFilterFunc filter)
+{
+    Unistr *unistr;
+    size_t i;
+    if (!str || !filter)
+    {
+        return NULL;
+    }
+
+    unistr = UnistrCreate("");
+    for (i = 0; i < UnistrSize(str); i++)
+    {
+        uint32_t code = UnistrGetch(str, i);
+        if (!filter(code))
+        {
+            continue;
+        }
+        UnistrAddch(unistr, code);
+    }
+
+    return unistr;
+}

src/XMPPThread/Stanzas/IQ.c

@@ -356,14 +356,14 @@ IQGet(ParseeData *args, XMLElement *stanza, XMPPThread *thr)
     }
     else if (XMLookForTKV(stanza, "vCard", "xmlns", "vcard-temp"))
     {
-        Log(LOG_INFO, "vCard information GET for %s", to);
+        char *to_matrix = ParseeGetBridgedUser(args, stanza);
+        char *name = ASGetName(args->config, NULL, to_matrix);
+        XMLElement *iqVCard;
+        Log(LOG_DEBUG, "vCard information GET for %s", to);
 
-        /* TODO: "a compliant server MUST respond on behalf of the 
-         * requestor and not forward the IQ to the requestee's 
-         * connected resource". */
         if (!strncmp(to, "parsee@", 7))
         {
-            XMLElement *iqVCard = XMLCreateTag("iq");
+            iqVCard = XMLCreateTag("iq");
             XMLAddAttr(iqVCard, "from", to);
             XMLAddAttr(iqVCard, "to", from);
             XMLAddAttr(iqVCard, "id", id);
@@ -394,7 +394,49 @@ IQGet(ParseeData *args, XMLElement *stanza, XMPPThread *thr)
             StreamFlush(jabber->stream);
             pthread_mutex_unlock(&jabber->write_lock);
             XMLFreeElement(iqVCard);
+            Free(to_matrix);
+            Free(name);
+            return;
         }
+
+        iqVCard = XMLCreateTag("iq");
+        XMLAddAttr(iqVCard, "from", to);
+        XMLAddAttr(iqVCard, "to", from);
+        XMLAddAttr(iqVCard, "id", id);
+        XMLAddAttr(iqVCard, "type", "result");
+        {
+            XMLElement *vCard = XMLCreateTag("vCard");
+            char *mto_link = ParseeGenerateMTO(to_matrix);
+            XMLAddAttr(vCard, "xmlns", "vcard-temp");
+            {
+                XMLElement *fn = CreateTagWithText(
+                    "FN", name ? name : to_matrix
+                );
+                XMLElement *nick = CreateTagWithText(
+                    "NICKNAME", to_matrix
+                );
+                XMLElement *url = CreateTagWithText(
+                    "URL", mto_link
+                );
+
+                /* TODO: Maybe abstract the vCard code. */
+                /* TODO: Make a function to just get a user's avatar
+                 * automatically. */
+                XMLAddChild(vCard, nick);
+                XMLAddChild(vCard, url);
+                XMLAddChild(vCard, fn);
+
+                Free(mto_link);
+            }
+            XMLAddChild(iqVCard, vCard);
+        }
+
+        pthread_mutex_lock(&jabber->write_lock);
+        XMLEncode(jabber->stream, iqVCard);
+        StreamFlush(jabber->stream);
+        pthread_mutex_unlock(&jabber->write_lock);
+        Free(to_matrix);
+        Free(name);
     }
 #define PS "http://jabber.org/protocol/pubsub"
     else if ((pubsub = XMLookForTKV(stanza, "pubsub", "xmlns", PS)))
@@ -417,8 +459,7 @@ IQGet(ParseeData *args, XMLElement *stanza, XMPPThread *thr)
             b64 = Base64Encode(buf, len);
             Free(buf);
 
-            Log(LOG_INFO, "FM=%s", to_matrix);
-            Log(LOG_INFO, "B=%s (%dB)", b64, (int) len);
+            Log(LOG_DEBUG, "IQ-GET: PUBSUB AVATAR OF=%s", to_matrix);
             /* Strike back with a response */
             reply = XMLCreateTag("iq");
             XMLAddAttr(reply, "type", "result");

src/include/Unistring.h

@@ -0,0 +1,67 @@
+#ifndef PARSEE_UNISTRING_H
+#define PARSEE_UNISTRING_H
+
+/*-* <p>A basic datastructure to handle Unicode strings easily.</p>
+ * <p>Mainly used because dealing with UTF-8 directly may be an 
+ * annoyance, and it may be used as a base for Cytoplasm's own 
+ * string management</p>
+ * --------
+ * Written-By: LDA 
+ * License: CC0 */
+
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+/* An opaque structure for a Unistring */
+typedef struct Unistr Unistr;
+
+/** Decodes an UTF-8 string into a separate Unistr.
+ * -------
+ * Returns: a valid Unistr[HEAP] | NULL
+ * Thrasher: UnistrFree */
+extern Unistr * UnistrCreate(char *src);
+
+/** Returns the length of an unistring.
+ * ----------
+ * Returns: the unistring's length | NULL */
+extern size_t UnistrSize(Unistr *unistr);
+
+/** Returns the character of an unistring at a location, 
+ * or 0 if it is inaccessible.
+ * ----------
+ * Returns: The Unicode codepoint of a specific 0-index | 0 */
+extern uint32_t UnistrGetch(Unistr *unistr, size_t i);
+
+/** Adds a singular codepoint to a unistring(IFF not 0 and valid).
+ * -------------
+ * Returns: NOTHING
+ * Modifies: unistr */
+extern void UnistrAddch(Unistr *unistr, uint32_t u);
+
+/** Encodes a unistring into a C UTF-8 string
+ * --------------
+ * Returns: a valid NULL-terminated string[HEAP] | NULL
+ * Thrasher: Free */
+extern char * UnistrC(Unistr *unistr);
+
+/** Destroys all memory associated with a unistring.
+ * ----------
+ * Returns: NOTHING
+ * Thrashes: {unistr} */
+extern void UnistrFree(Unistr *unistr);
+
+/** Returns true IFF the character is within the unicode BMP and 
+ * not 0x0000
+ * ------------------------------------------------------------
+ * Returns: whenever the character is within the BMP */
+extern bool UnistrIsBMP(uint32_t u);
+
+typedef bool (*UnistrFilterFunc)(uint32_t u);
+/** "Filters" characters in a Unistring by codepoint, removing 
+ * those with callbacks which return false into a new unistring.
+ * --------------------
+ * Returns: a new unistring with filtered characters removed */
+extern Unistr * UnistrFilter(Unistr *str, UnistrFilterFunc filter);
+
+#endif