Working on improving the network handling.

5 files changed, 211 insertions, 61 deletions

diff --git a/src/core/assimilate.c b/src/core/assimilate.c
index eb6aa17..28f4dd4 100644
--- a/src/core/assimilate.c
+++ b/src/core/assimilate.c
@@ -5,6 +5,8 @@
 
 #include "knowledge.h"
 
+/** Functions to assimilate sentences using a ZoO_knowledge structure *********/
+
 static int link_to
 (
    ZoO_index links_count [const restrict static 1],
diff --git a/src/core/create_sentences.c b/src/core/create_sentences.c
index bc410e5..e999199 100644
--- a/src/core/create_sentences.c
+++ b/src/core/create_sentences.c
@@ -7,6 +7,17 @@
 
 #include "knowledge.h"
 
+/** Functions to create sentences using a ZoO_knowledge structure *************/
+
+/*
+ * Returns the index of a element in {links} chosen randomly according
+ * to the distribution in {links_occurrences}.
+ * Pre:
+ *    (!= occurrences 0).
+ *    (== (length links_occurrences) (length links)).
+ *    (== (sum links_occurrences) occurrences).
+ *    (can_store ZoO_index (length links)).
+ */
 static ZoO_index pick_an_index
 (
    ZoO_index const occurrences,
@@ -17,29 +28,40 @@ static ZoO_index pick_an_index
    ZoO_index result, accumulator, random_number;
 
    result = 0;
+
+   /*
+    * Safe:
+    * (> (length links_occurrences) 0).
+    */
    accumulator = links_occurrences[0];
+
    random_number = (((ZoO_index) rand()) % occurrences);
 
    while (accumulator < random_number)
    {
-
       /*
-       * Should be safe:
-       * result overflowing <-> sum('links_occurrences') > 'occurrences'
-       * and sum('links_occurrences') == 'occurrences'
+       * Safe:
+       * (->
+       *    (and
+       *       (== accumulator (sum links_occurrences[0:result]))
+       *       (< accumulator random_number)
+       *       (< random_number occurrences)
+       *       (== occurrences (sum links_occurrences))
+       *       (can_store ZoO_index (length links))
+       *       (== (length links_occurrences) (length links))
+       *    )
+       *    (and
+       *       (< result' (length links_occurrences))
+       *       (can_store ZoO_index result')
+       *       (=< accumulator' occurrences)
+       *    )
+       * )
        */
       result += 1;
-
-      /*
-       * Should be safe:
-       *  - sum('links_occurrences') == 'occurrences'.
-       *  - 'occurrences' is safe.
-       *  ----
-       *  'accumulator' is safe.
-       */
       accumulator += links_occurrences[result];
    }
 
+   /* Safe: (< result (length links)) */
    return links[result];
 }
 
@@ -330,7 +352,7 @@ static unsigned char * extend_right
 int ZoO_knowledge_extend
 (
    struct ZoO_knowledge k [const static 1],
-   const struct ZoO_strings string [const static 1],
+   const struct ZoO_strings string [const],
    int const ignore_first_word,
    ZoO_char * result [const static 1]
 )
@@ -339,48 +361,56 @@ int ZoO_knowledge_extend
    size_t sentence_size;
    ZoO_index i, word_id, word_min_score, word_min_id, credits;
 
-   word_found = 0;
    credits = ZoO_MAX_REPLY_WORDS;
 
-   if (ignore_first_word)
-   {
-      i = 1;
-   }
-   else
+   if (string != (struct ZoO_strings *) NULL)
    {
-      i = 0;
-   }
+      word_found = 0;
 
-   for (; i < string->words_count; ++i)
-   {
-      /* prevents k [restrict] */
-      if (ZoO_knowledge_find(k, string->words[i], &word_min_id) == 0)
+      if (ignore_first_word)
       {
-         word_found = 1;
-         word_min_score = k->words[word_min_id].occurrences;
+         i = 1;
+      }
+      else
+      {
+         i = 0;
+      }
 
-         break;
+      for (; i < string->words_count; ++i)
+      {
+         /* prevents k [restrict] */
+         if (ZoO_knowledge_find(k, string->words[i], &word_min_id) == 0)
+         {
+            word_found = 1;
+            word_min_score = k->words[word_min_id].occurrences;
+
+            break;
+         }
       }
-   }
 
-   if (word_found == 0)
-   {
-      word_min_id = (rand() % k->words_count);
-      word_min_score = k->words[word_min_id].occurrences;
-   }
+      if (word_found == 0)
+      {
+         word_min_id = (rand() % k->words_count);
+         word_min_score = k->words[word_min_id].occurrences;
+      }
 
-   for (; i < string->words_count; ++i)
-   {
-      if
-      (
-         (ZoO_knowledge_find(k, string->words[i], &word_id) == 0)
-         && (k->words[word_id].occurrences < word_min_score)
-      )
+      for (; i < string->words_count; ++i)
       {
-         word_min_score = k->words[word_id].occurrences;
-         word_min_id = word_id;
+         if
+         (
+            (ZoO_knowledge_find(k, string->words[i], &word_id) == 0)
+            && (k->words[word_id].occurrences < word_min_score)
+         )
+         {
+            word_min_score = k->words[word_id].occurrences;
+            word_min_id = word_id;
+         }
       }
    }
+   else
+   {
+      word_min_id = (rand() % k->words_count);
+   }
 
    /* 3: 2 spaces + '\0' */
    /* FIXME: not overflow-safe */
diff --git a/src/core/knowledge.c b/src/core/knowledge.c
index 31ccb97..9b4e250 100644
--- a/src/core/knowledge.c
+++ b/src/core/knowledge.c
@@ -6,6 +6,8 @@
 
 #include "knowledge.h"
 
+/** Basic functions of the ZoO_knowledge structure ****************************/
+
 /* XXX: are we as close to immutable as we want to be? */
 unsigned int const ZoO_knowledge_punctuation_chars_count = 7;
 const ZoO_char const ZoO_knowledge_punctuation_chars[7] =
@@ -33,6 +35,7 @@ const ZoO_char const ZoO_knowledge_forbidden_chars[8]=
       '>'
    };
 
+/* See "knowledge.h". */
 int ZoO_knowledge_find
 (
    const struct ZoO_knowledge k [const restrict static 1],
@@ -54,7 +57,7 @@ int ZoO_knowledge_find
 
    current_min = 0;
 
-   /* overflow-safe: k->words_count >= 1 */
+   /* Safe: (>= k->words_count 1) */
    current_max = (k->words_count - 1);
 
    for (;;)
@@ -124,6 +127,18 @@ static void word_init (struct ZoO_knowledge_word w [const restrict static 1])
    w->backward_links = (ZoO_index *) NULL;
 }
 
+/*
+ * When returning 0:
+ *    All punctuation symbols were added to {k}.
+ * When returning -1:
+ *    The mandatory punctuation symbols have been added to {k}, but some of the
+ *    additional ones did not. This does not prevent ZoO from working, but
+ *    will result in some punctuation symbols to be handled exactly like
+ *    common words.
+ * When returning -2:
+ *    The mandatory punctuation symbols have not added to {k}. ZoO will not be
+ *    able to work.
+ */
 static int add_punctuation_nodes
 (
    struct ZoO_knowledge k [const static 1]
@@ -177,6 +192,7 @@ static int add_punctuation_nodes
    return error;
 }
 
+/* See "knowledge.h" */
 int ZoO_knowledge_initialize (struct ZoO_knowledge k [const static 1])
 {
    k->words_count = 0;
@@ -193,6 +209,10 @@ int ZoO_knowledge_initialize (struct ZoO_knowledge k [const static 1])
    return 0;
 }
 
+/*
+ * Frees all the memory used by {w}, but not {w} itself.
+ * The values of {w}'s members are set to reflect the changes.
+ */
 static void finalize_word
 (
    struct ZoO_knowledge_word w [const restrict static 1]
@@ -237,13 +257,13 @@ static void finalize_word
    w->backward_links_count = 0;
 }
 
+/* See "knowledge.h" */
 void ZoO_knowledge_finalize (struct ZoO_knowledge k [const restrict static 1])
 {
    ZoO_index i;
 
    for (i = 0; i < k->words_count; ++i)
    {
-      /* prevents k [restrict] */
       finalize_word(k->words + i);
    }
 
@@ -264,6 +284,7 @@ void ZoO_knowledge_finalize (struct ZoO_knowledge k [const restrict static 1])
    }
 }
 
+/* See "knowledge.h" */
 int ZoO_knowledge_learn
 (
    struct ZoO_knowledge k [const static 1],
@@ -291,7 +312,7 @@ int ZoO_knowledge_learn
          return -1;
       }
 
-      /* overflow-safe */
+      /* overflow-safe: (< k->words[*result].occurrences ZoO_INDEX_MAX) */
       k->words[*result].occurrences += 1;
 
       return 0;
@@ -310,7 +331,7 @@ int ZoO_knowledge_learn
          (void *) k->words,
          (
             (
-               /* overflow-safe: k->words_count < ZoO_INDEX_MAX */
+               /* overflow-safe: (< k->words_count ZoO_INDEX_MAX) */
                (size_t) (k->words_count + 1)
             )
             * sizeof(struct ZoO_knowledge_word)
@@ -336,7 +357,7 @@ int ZoO_knowledge_learn
          (void *) k->sorted_indices,
          (
             (
-               /* overflow-safe: k->words_count < ZoO_INDEX_MAX */
+               /* overflow-safe: (< k->words_count ZoO_INDEX_MAX) */
                (size_t) (k->words_count + 1)
             )
             * sizeof(ZoO_index)
@@ -359,22 +380,27 @@ int ZoO_knowledge_learn
    k->sorted_indices = new_sorted_indices;
 
    /* We can only move indices right of *result if they exist. */
-   if (*result != k->words_count)
+   if (*result < k->words_count)
    {
       /* TODO: check if correct. */
       memmove
       (
          /*
-          * overflow-safe:
-          *  - k->words_count < ZoO_INDEX_MAX
-          *  - (k->sorted_indices + *result + 1) =< k->words_count
+          * Safe:
+          *  (->
+          *    (and
+          *       (== (length k->sorted_indices) (+ k->words_count 1))
+          *       (< *result k->words_count)
+          *    )
+          *    (< (+ *result 1) (length k->sorted_indices))
+          * )
           */
          (void *) (k->sorted_indices + *result + 1),
-         /* overflow-safe: see above */
+         /* Safe: see above */
          (const void *) (k->sorted_indices + *result),
          (
             (
-               /* overflow-safe: *result < k->words_count */
+               /* Safe: (< *result k->words_count) */
                (size_t) (k->words_count - *result)
             )
             * sizeof(ZoO_index)
diff --git a/src/core/knowledge.h b/src/core/knowledge.h
index f20cb16..c9ea342 100644
--- a/src/core/knowledge.h
+++ b/src/core/knowledge.h
@@ -5,10 +5,35 @@
 
 #include "knowledge_types.h"
 
+/*
+ * Initializes all of {k}'s members to sane values.
+ *
+ * When returning 0:
+ *    Initial punctuation nodes (including the mandatory "START OF LINE" and
+ *    "END OF LINE" ones) have successfully been added to {k}.
+ *
+ * When return -1:
+ *    Something went wrong, leading to {k} not being safe for use.
+ *    {k} has been finalized.
+ */
 int ZoO_knowledge_initialize (struct ZoO_knowledge k [const static 1]);
 
+/*
+ * Frees all the memory used by {k}, but not {k} itself.
+ * The values of {k}'s members are set to reflect the changes.
+ */
 void ZoO_knowledge_finalize (struct ZoO_knowledge k [const static 1]);
 
+/*
+ * When returning 0:
+ *    {word} is in {k}.
+ *    {word} is located at {k->words[*result]}.
+ *
+ * When returning -1:
+ *    {word} is not in {k}.
+ *    {*result} is where {word} was expected to be found in
+ *    {k->sorted_indices}.
+ */
 int ZoO_knowledge_find
 (
    const struct ZoO_knowledge k [const restrict static 1],
@@ -16,6 +41,17 @@ int ZoO_knowledge_find
    ZoO_index result [const restrict static 1]
 );
 
+/*
+ * When returning 0:
+ *    {word} was either added to {k} or its representation in {k} has its
+ *    occurrences count increased.
+ *    {*result} indicates where {word} is in {k->words}.
+ *
+ * When returning -1:
+ *    Something went wrong when adding the occurrence of {word} to {k}.
+ *    {k} remains semantically unchanged.
+ *    {*result} may or may not have been altered.
+ */
 int ZoO_knowledge_learn
 (
    struct ZoO_knowledge k [const static 1],
@@ -34,7 +70,7 @@ int ZoO_knowledge_assimilate
 int ZoO_knowledge_extend
 (
    struct ZoO_knowledge k [const static 1],
-   const struct ZoO_strings string [const static 1],
+   const struct ZoO_strings string [const],
    int const ignore_first_word,
    ZoO_char * result [const static 1]
 );
diff --git a/src/core/main.c b/src/core/main.c
index 40b3705..1a8a40f 100644
--- a/src/core/main.c
+++ b/src/core/main.c
@@ -150,6 +150,43 @@ static int should_reply
    return (param->reply_rate >= (rand() % 100));
 }
 
+static void handle_user_join
+(
+   struct ZoO_state s [const static 1]
+)
+{
+   ZoO_char * line;
+
+   if
+   (
+      (s->param.reply_rate >= (rand() % 100))
+      &&
+      (
+         ZoO_knowledge_extend
+         (
+            &(s->knowledge),
+            (struct ZoO_strings *) NULL,
+            0,
+            &line
+         ) == 0
+      )
+   )
+   {
+      if (line[0] == ' ')
+      {
+         strcpy((s->network.out), (line + 1));
+      }
+      else
+      {
+         strcpy((s->network.out), line);
+      }
+
+      free((void *) line);
+
+      ZoO_network_send(&(s->network));
+   }
+}
+
 static void handle_message
 (
    struct ZoO_state s [const static 1],
@@ -167,7 +204,7 @@ static void handle_message
       (
          string,
          (size_t) msg_size,
-         (s->network.msg + msg_offset),
+         (s->network.in + msg_offset),
          ZoO_knowledge_punctuation_chars_count,
          ZoO_knowledge_punctuation_chars
       ) < 0
@@ -202,11 +239,11 @@ static void handle_message
    {
       if (line[0] == ' ')
       {
-         strcpy((s->network.msg), (line + 1));
+         strcpy((s->network.out), (line + 1));
       }
       else
       {
-         strcpy((s->network.msg), line);
+         strcpy((s->network.out), line);
       }
 
       free((void *) line);
@@ -226,10 +263,11 @@ static void handle_message
    }
 }
 
-static int main_loop  (struct ZoO_state s [const static 1])
+static int main_loop (struct ZoO_state s [const static 1])
 {
    struct ZoO_strings string;
    ssize_t msg_offset, msg_size;
+   enum ZoO_msg_type msg_type;
 
    msg_offset = 0;
    msg_size = 0;
@@ -238,9 +276,27 @@ static int main_loop  (struct ZoO_state s [const static 1])
 
    while (run)
    {
-      if (ZoO_network_receive(&(s->network), &msg_offset, &msg_size) == 0)
+      if
+      (
+         ZoO_network_receive
+         (
+            &(s->network),
+            &msg_offset,
+            &msg_size,
+            &msg_type
+         ) == 0
+      )
       {
-         handle_message(s, &string, msg_offset, msg_size);
+         switch (msg_type)
+         {
+            case ZoO_JOIN:
+               handle_user_join(s);
+               break;
+
+            case ZoO_PRIVMSG:
+               handle_message(s, &string, msg_offset, msg_size);
+               break;
+         }
       }
    }