Added cstr_append_fmt().

4 files changed, 25 insertions, 15 deletions

diff --git a/docs/cstr_api.md b/docs/cstr_api.md
index 273f4de4..3d9aae85 100644
--- a/docs/cstr_api.md
+++ b/docs/cstr_api.md
@@ -57,6 +57,7 @@ char*        cstr_append(cstr* self, const char* str);
 char*        cstr_append_n(cstr* self, const char* str, size_t n);    // append n first bytes of str
 char*        cstr_append_sv(cstr* self, csview str);
 char*        cstr_append_s(cstr* self, cstr str);
+int          cstr_append_fmt(const char* fmt, ...);                   // printf() formatting
 char*        cstr_append_uninit(cstr* self, size_t len);              // append len uninitialized bytes
 
 void         cstr_insert(cstr* self, size_t pos, const char* ins);
diff --git a/examples/box2.c b/examples/box2.c
index 75f9970f..28b4acff 100644
--- a/examples/box2.c
+++ b/examples/box2.c
@@ -35,7 +35,7 @@ Point origin(void) {
 
 cbox_Point boxed_origin(void) {
     // Allocate this point on the heap, and return a pointer to it
-    return cbox_Point_make((Point){ .x=0.0, .y=0.0 });
+    return cbox_Point_from((Point){ .x=0.0, .y=0.0 });
 }
 
 
@@ -53,16 +53,16 @@ int main(void) {
     c_auto (cbox_BoxPoint, box_in_a_box)
     {
         // Heap allocated rectangle
-        boxed_rectangle = cbox_Rectangle_make((Rectangle){
+        boxed_rectangle = cbox_Rectangle_from((Rectangle){
             .top_left = origin(),
             .bottom_right = (Point){ .x=3.0, .y=-4.0 }
         });
 
         // The output of functions can be boxed
-        boxed_point = cbox_Point_make(origin());
+        boxed_point = cbox_Point_from(origin());
 
         // Double indirection
-        box_in_a_box = cbox_BoxPoint_make(boxed_origin());
+        box_in_a_box = cbox_BoxPoint_from(boxed_origin());
 
         printf("Point occupies %" PRIuMAX " bytes on the stack\n",
                 sizeof(point));
diff --git a/examples/new_sptr.c b/examples/new_sptr.c
index 71222799..e3431d8a 100644
--- a/examples/new_sptr.c
+++ b/examples/new_sptr.c
@@ -2,7 +2,7 @@
 
 struct Person { cstr name, last; } typedef Person;
 
-Person Person_new(const char* name, const char* last) {
+Person Person_from(const char* name, const char* last) {
     return (Person){.name = cstr_from(name), .last = cstr_from(last)};
 }
 Person Person_clone(Person p) {
@@ -32,18 +32,18 @@ int main(void) {
     c_auto (carc_person, p, q, r, s)
     {
         puts("Ex1");
-        p = carc_person_make(Person_new("John", "Smiths"));
+        p = carc_person_from(Person_from("John", "Smiths"));
         q = carc_person_clone(p);
         r = carc_person_clone(p);
-        s = carc_person_make(Person_clone(*p.get)); // deep copy
+        s = carc_person_from(Person_clone(*p.get)); // deep copy
         printf("%s %s. uses: %lu\n", cstr_str(&r.get->name), cstr_str(&s.get->last), *p.use_count);
     }
 
     c_auto (cstack_iptr, stk) {
         puts("Ex2");
-        cstack_iptr_push(&stk, SPtr_make(10));
-        cstack_iptr_push(&stk, SPtr_make(20));
-        cstack_iptr_push(&stk, SPtr_make(30));
+        cstack_iptr_push(&stk, SPtr_from(10));
+        cstack_iptr_push(&stk, SPtr_from(20));
+        cstack_iptr_push(&stk, SPtr_from(30));
         cstack_iptr_push(&stk, SPtr_clone(*cstack_iptr_top(&stk)));
         cstack_iptr_push(&stk, SPtr_clone(*cstack_iptr_begin(&stk).ref));
 
diff --git a/include/stc/cstr.h b/include/stc/cstr.h
index fe253c71..983c3d4b 100644
--- a/include/stc/cstr.h
+++ b/include/stc/cstr.h
@@ -87,6 +87,7 @@ STC_API bool    cstr_getdelim(cstr *self, int delim, FILE *fp);
 STC_API void    cstr_erase(cstr* self, size_t pos, size_t len);
 STC_API void    cstr_u8_erase(cstr* self, size_t bytepos, size_t u8len);
 STC_API cstr    cstr_from_fmt(const char* fmt, ...);
+STC_API int     cstr_append_fmt(cstr* self, const char* fmt, ...);
 STC_API int     cstr_printf(cstr* self, const char* fmt, ...);
 STC_API void    cstr_replace(cstr* self, const char* search, const char* repl, unsigned count);
 STC_API cstr    cstr_replace_sv(csview sv, csview search, csview repl, unsigned count);
@@ -563,13 +564,13 @@ STC_DEF void cstr_u8_erase(cstr* self, const size_t bytepos, const size_t u8len)
 #  pragma warning(disable: 4996)
 #endif
 
-STC_DEF int cstr_vfmt(cstr* self, const char* fmt, va_list args) {
+STC_DEF int cstr_vfmt(cstr* self, size_t start, const char* fmt, va_list args) {
     va_list args2;
     va_copy(args2, args);
     const int n = vsnprintf(NULL, (size_t)0, fmt, args);
-    vsprintf(cstr_reserve(self, n), fmt, args2);
+    vsprintf(cstr_reserve(self, start + n) + start, fmt, args2);
     va_end(args2);
-    _cstr_set_size(self, n);
+    _cstr_set_size(self, start + n);
     return n;
 }
 #if defined(__clang__)
@@ -582,16 +583,24 @@ STC_DEF cstr cstr_from_fmt(const char* fmt, ...) {
     cstr s = cstr_null;
     va_list args;
     va_start(args, fmt);
-    cstr_vfmt(&s, fmt, args);
+    cstr_vfmt(&s, 0, fmt, args);
     va_end(args);
     return s;
 }
 
+STC_DEF int cstr_append_fmt(cstr* self, const char* fmt, ...) {
+    va_list args;
+    va_start(args, fmt);
+    const int n = cstr_vfmt(self, cstr_size(self), fmt, args);
+    va_end(args);
+    return n;
+}
+
 /* NB! self-data in args is UB */
 STC_DEF int cstr_printf(cstr* self, const char* fmt, ...) {
     va_list args;
     va_start(args, fmt);
-    const int n = cstr_vfmt(self, fmt, args);
+    const int n = cstr_vfmt(self, 0, fmt, args);
     va_end(args);
     return n;
 }