From ef2b51d6f0c6fc351528b8fce88dbf58dd53966c Mon Sep 17 00:00:00 2001
From: =?utf8?q?Vin=C3=ADcius=20R=2E=20Miguel?= <lemao.vrm07@hotmail.com>
Date: Sat, 6 Jun 2020 03:25:53 -0300
Subject: [PATCH] Fix a FIXME and add WIP string_concat

---
 src/libstring.c | 40 ++++++++++++++++++++++++++++++++++------
 src/libstring.h |  4 ++--
 test/main.c     |  6 ++++++
 3 files changed, 42 insertions(+), 8 deletions(-)

diff --git a/src/libstring.c b/src/libstring.c
index 1898699..b423939 100644
--- a/src/libstring.c
+++ b/src/libstring.c
@@ -130,12 +130,12 @@ char * __memcpy(char * dest, const char *src, size_t n) {
 //! \param src       Source char array.
 //! \param size      Quantitity of elements to be copied. It may be larger than __strlen(src), but the function will not write more than __strlen(src).
 //!
-void __strcpy(char *dest, const char *src, size_t size)
+size_t __strcpy(char *dest, const char *src, size_t size)
 {
     if(!size)
     {
         fprintf(stderr, "__strcpy should not be called with size==0\n");
-        return;
+        return 0;
     }
 
     size_t source_len = __strlen(src);
@@ -151,6 +151,17 @@ void __strcpy(char *dest, const char *src, size_t size)
 
     __memcpy(dest, src, n);      // Copy the contents of src to dest
     dest[n] = '\0';              // Null-terminate dest.
+    return source_len;
+}
+
+size_t __strcat(char *dest, const char *src, size_t size)
+{
+    size_t dest_len = __strlen(dest);
+    if (dest_len < size)
+    {
+        return(dest_len + __strcpy(dest + dest_len, src, size - dest_len));
+    }
+    return(dest_len + __strlen(src));
 }
 
 /*!
@@ -180,7 +191,7 @@ cstr_t * string_alloc (size_t nbytes)
         alloc_list_head                = __malloc(sizeof(struct alloc_node));
         alloc_list_head->val           = __malloc(sizeof(struct cstr));
         alloc_list_head->val->value    = __malloc(nbytes * sizeof(char));
-        alloc_list_head->val->size     = nbytes;
+        alloc_list_head->val->size     = nbytes-1;  //! Remove one from nbytes because it includes the NULL-terminator.
         alloc_list_head->val->reserved = nbytes;
         alloc_list_head->next          = NULL;
         return alloc_list_head->val;
@@ -362,6 +373,25 @@ bool string_reserve(cstr_t *str, size_t capacity)
     return true;
 }
 
+    //! This function is a work-in-progress!
+cstr_t * string_concat(cstr_t * str1, const char * str2)
+{
+    cstr_t * new = string_init(str1->value);
+
+    size_t str2len = __strlen(str2);
+    if(new->reserved < str1->size + str2len)
+    {
+        if(!string_reserve(new, new->size + str2len + 1))
+        {
+            fprintf(stderr, "In string_concat: string_reserve failed.\n");
+            return new;
+        }
+    }
+    __strcat(new->value, str2, str2len);
+    new->size = str1->size + str2len;
+    return new;
+}
+
 //!
 //! \brief string_replace_char Replaces all instances of `before` in str to `after`.
 //! \param str                 The cstr_t * to be altered.
@@ -381,9 +411,7 @@ size_t string_replace_char(cstr_t *str, char before, char after)
 
     size_t i, modified = 0;
 
-    size_t str_len = __strlen(str->value);  // TODO: I'm doing this because I think size is sometimes is counting the NUL character. FIXME
-
-    for(i=0; i < str_len; i++)
+    for(i=0; i < str->size; i++)
     {
         if(str->value[i] == before)
         {
diff --git a/src/libstring.h b/src/libstring.h
index ca6187b..56a6b1e 100644
--- a/src/libstring.h
+++ b/src/libstring.h
@@ -52,8 +52,8 @@ void string_free_all(void);                                // def, tested, unfin
 
 // Utility functions
 int string_compare(cstr_t * str1, cstr_t * str2);          // undef, Follows C++ standard
-cstr_t * string_concat(cstr_t * str1, cstr_t * str2);      // undef, returns str1 + str2
-size_t string_concat_to(cstr_t * str1, cstr_t * str2);     // undef, str1 = str1 + str2
+cstr_t * string_concat(cstr_t * str1, const char * str2);  // undef, returns str1 + str2
+size_t string_concat_to(cstr_t * str1, const char * str2); // undef, str1 = str1 + str2
 bool string_ends_with_x(cstr_t * str, cstr_t * x);         // undef
 char string_get_char_at(cstr_t * str, size_t pos);         // undef, bound-checking
 size_t string_index_of(cstr_t *str, char c);               // undef
diff --git a/test/main.c b/test/main.c
index 68b51b6..1e344de 100644
--- a/test/main.c
+++ b/test/main.c
@@ -53,6 +53,12 @@ int main(void)
     {
         printf("%s is in %s\n", "armes", str1->value);
     }
+
+    //! Testing string_concat(cstr_t *, const char *)
+    printf("\nTesting string_concat(cstr_t *, const char *)\n");
+    cstr_t * concat = string_concat(str1, " project");
+    printf("str1 + \" project\" = %s\n", concat->value);
+
     //!
     string_free_all();
 }
-- 
2.11.4.GIT