1 files changed, 196 insertions, 0 deletions
diff --git a/src/sequence/sequence_to_string.c b/src/sequence/sequence_to_string.c
new file mode 100644
index 0000000..6794fcb
--- /dev/null
+++ b/src/sequence/sequence_to_string.c
@@ -0,0 +1,196 @@
+#define _POSIX_C_SOURCE 200809L
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h> /* defines SIZE_MAX */
+
+#include "../core/char.h"
+#include "../core/index.h"
+
+#include "../error/error.h"
+
+#include "../knowledge/knowledge.h"
+
+#include "sequence.h"
+
+/******************************************************************************/
+/** MEMORY ALLOCATION *********************************************************/
+/******************************************************************************/
+static int ensure_string_capacity
+(
+   JH_char * string [const restrict static 1],
+   size_t string_capacity [const restrict static 1],
+   const size_t string_required_capacity,
+   FILE io [const restrict static 1]
+)
+{
+   JH_char * new_string;
+
+   if (string_required_capacity <= *string_capacity)
+   {
+      return 0;
+   }
+
+   new_string =
+      (JH_char *) realloc
+      (
+         (void *) *string,
+         ((size_t) string_required_capacity) * sizeof(JH_char)
+      );
+
+   if (new_string== (JH_char *) NULL)
+   {
+      JH_S_ERROR
+      (
+         io,
+         "Unable to reallocate memory to match string's required size."
+      );
+
+      return -1;
+   }
+
+   *string_capacity = string_required_capacity;
+   *string = new_string;
+
+   return 1;
+}
+
+/******************************************************************************/
+/** ADD WORD ******************************************************************/
+/******************************************************************************/
+static int increment_required_capacity
+(
+   size_t current_capacity [const restrict static 1],
+   const size_t increase_factor,
+   FILE io [const restrict static 1]
+)
+{
+   if ((JH_INDEX_MAX - increase_factor) < *current_capacity)
+   {
+      JH_S_ERROR
+      (
+         io,
+         "String capacity increment aborted, as the new capacity would not "
+         "fit in a JH_index variable."
+      );
+
+      return -1;
+   }
+
+   *current_capacity += increase_factor;
+
+   if ((SIZE_MAX / sizeof(JH_char)) < *current_capacity)
+   {
+      *current_capacity -= increase_factor;
+
+      JH_S_ERROR
+      (
+         io,
+         "String capacity increment aborted, as the new size would not fit "
+         "in a size_t variable."
+      );
+
+      return -2;
+   }
+
+   return 0;
+}
+
+static int add_word
+(
+   const JH_index word_id,
+   struct JH_knowledge k [const restrict static 1],
+   JH_char * destination [const restrict static 1],
+   size_t destination_capacity [const restrict static 1],
+   size_t destination_length [const restrict static 1],
+   FILE io [const restrict static 1]
+)
+{
+   const JH_char * word;
+   JH_index word_size;
+   size_t insertion_point;
+
+   if (word_id < JH_RESERVED_IDS_COUNT)
+   {
+      return 0;
+   }
+
+   (void) JH_knowledge_lock_access(k, io);
+   JH_knowledge_get_word(k, word_id, &word, &word_size);
+   (void) JH_knowledge_unlock_access(k, io);
+
+   insertion_point = *destination_length;
+
+   /* word_size includes '\n', which will be replaced by a space. */
+   /* (word_size == JH_INDEX_MAX) ==> could not have learned word. */
+   if (increment_required_capacity(destination_length, (word_size + 1), io) < 0)
+   {
+      return -1;
+   }
+
+   if
+   (
+      ensure_string_capacity
+      (
+         destination,
+         destination_capacity,
+         *destination_length,
+         io
+      ) < 0
+   )
+   {
+      return -2;
+   }
+
+   memcpy
+   (
+      (*destination + insertion_point),
+      (const void *) word,
+      word_size
+   );
+
+   (*destination)[*destination_length - 1] = ' ';
+
+   return 0;
+}
+
+/******************************************************************************/
+/** EXPORTED ******************************************************************/
+/******************************************************************************/
+int JH_sequence_to_undercase_string
+(
+   const JH_index sequence [const restrict static 1],
+   const size_t sequence_length,
+   struct JH_knowledge k [const restrict static 1],
+   JH_char * destination [const restrict static 1],
+   size_t destination_capacity [const restrict static 1],
+   size_t destination_length [const restrict static 1],
+   FILE io [const restrict static 1]
+)
+{
+   size_t i;
+
+   *destination_length = 0;
+
+   for (i = 0; i < sequence_length; ++i)
+   {
+      if
+      (
+         add_word
+         (
+            sequence[i],
+            k,
+            destination,
+            destination_capacity,
+            destination_length,
+            io
+         ) < 0
+      )
+      {
+         *destination_length = 0;
+
+         return -1;
+      }
+   }
+
+   return 0;
+}