sync,szip,term,time,x.ttf: prepare for making -W impure-v the default (#19929)

vlib/term/utf8.c.v

@@ -1,6 +0,0 @@
-module term
-
-@[inline]
-fn getchar() int {
-	return C.getchar()
-}

vlib/term/utf8.v

@@ -2,8 +2,8 @@ module term
 
 // utf8_getchar returns an utf8 rune from standard input
 pub fn utf8_getchar() ?rune {
-	c := getchar()
-	if c == C.EOF {
+	c := input_character()
+	if c == -1 {
 		return none
 	}
 	len := utf8_len(u8(~c))
@@ -16,7 +16,7 @@ pub fn utf8_getchar() ?rune {
 	} else {
 		mut uc := c & ((1 << (7 - len)) - 1)
 		for i := 0; i + 1 < len; i++ {
-			c2 := getchar()
+			c2 := input_character()
 			if c2 != -1 && (c2 >> 6) == 2 {
 				uc <<= 6
 				uc |= (c2 & 63)

vlib/x/ttf/common.v

@@ -88,7 +88,7 @@ fn (mut bmp BitMap) format_texture() {
 pub fn (mut bmp BitMap) save_as_ppm(file_name string) {
 	tmp_buf := bmp.buf
 	mut buf := unsafe { malloc_noscan(bmp.buf_size) }
-	unsafe { C.memcpy(buf, tmp_buf, bmp.buf_size) }
+	unsafe { vmemcpy(buf, tmp_buf, bmp.buf_size) }
 	bmp.buf = buf
 
 	bmp.format_texture()

vlib/x/ttf/render_bmp.v

@@ -54,7 +54,7 @@ pub mut:
 pub fn (mut bmp BitMap) clear() {
 	mut sz := bmp.width * bmp.height * bmp.bp
 	unsafe {
-		C.memset(bmp.buf, 0x00, sz)
+		vmemset(bmp.buf, 0x00, sz)
 	}
 }