ncmetric: adapt PREFIXFMT to multibyte #630

include/notcurses/notcurses.h

@@ -2339,23 +2339,22 @@ API void* nctablet_userptr(struct nctablet* t);
 // Access the ncplane associated with this nctablet, if one exists.
 API struct ncplane* nctablet_ncplane(struct nctablet* t);
 
-// The number of columns is one fewer, as the expressions here must
-// leave an extra byte open in case “µ” (U+00B5, 0xC2 0xB5) shows up.
+// The number of columns is one fewer, as the STRLEN expressions must
+// leave an extra byte open in case 'µ' (U+00B5, 0xC2 0xB5) shows up.
 #define PREFIXCOLUMNS 7
 #define IPREFIXCOLUMNS 8
 #define BPREFIXCOLUMNS 9
-
 #define PREFIXSTRLEN (PREFIXCOLUMNS + 1)  // Does not include a '\0' (xxx.xxU)
 #define IPREFIXSTRLEN (IPREFIXCOLUMNS + 1) //  Does not include a '\0' (xxxx.xxU)
 #define BPREFIXSTRLEN (BPREFIXCOLUMNS + 1) // Does not include a '\0' (xxxx.xxUi), i == prefix
-
-// A bit of the nasties here to stringize our preprocessor tokens just now
-// #defined, making them usable as printf(3) specifiers.
-#define STRHACK1(x) #x
-#define STRHACK2(x) STRHACK1(x)
-#define PREFIXFMT "%" STRHACK2(PREFIXCOLUMNS) "s"
-#define IPREFIXFMT "%" STRHACK2(IPREFIXCOLUMNS) "s"
-#define BPREFIXFMT "%" STRHACK2(BPREFIXCOLUMNS) "s"
+// Used as arguments to a variable field width (i.e. "%*s" -- these are the *).
+// We need this convoluted grotesquery to properly handle 'µ'.
+#define PREFIXFWIDTH(x) ((int)(strlen(x) - mbswidth(x) + PREFIXCOLUMNS))
+#define IPREFIXFWIDTH(x) ((int)(strlen(x) - mbswidth(x) + IPREFIXCOLUMNS))
+#define BPREFIXFWIDTH(x) ((int)(strlen(x) - mbswidth(x) + BPREFIXCOLUMNS))
+#define PREFIXFMT(x) PREFIXFWIDTH(x), x
+#define IPREFIXFMT(x) IPREFIXFWIDTH(x), x
+#define BPREFIXFMT(x) BPREFIXFWIDTH(x), x
 
 // Takes an arbitrarily large number, and prints it into a fixed-size buffer by
 // adding the necessary SI suffix. Usually, pass a |[IB]PREFIXSTRLEN+1|-sized

src/demo/demo.c

@@ -369,10 +369,8 @@ summary_table(struct ncdirect* nc, const char* spec){
     printf("%9s", demos[results[i].selector - 'a'].name);
     ncdirect_fg_rgb8(nc, 178, 102, 255);
     printf("│%*ss│%7ju│%*s│ %*ss│%3jd│%7.1f│%7.1f║",
-           PREFIXCOLUMNS, timebuf,
-           (uintmax_t)(results[i].stats.renders),
-           BPREFIXCOLUMNS, totalbuf,
-           PREFIXCOLUMNS, rtimebuf,
+           PREFIXFMT(timebuf), (uintmax_t)(results[i].stats.renders),
+           BPREFIXFMT(totalbuf), PREFIXFMT(rtimebuf),
            (uintmax_t)(results[i].timens ?
             results[i].stats.render_ns * 100 / results[i].timens : 0),
            results[i].timens ?
@@ -395,10 +393,10 @@ summary_table(struct ncdirect* nc, const char* spec){
   qprefix(totalrenderns, GIG, rtimebuf, 0);
   table_segment(nc, "", "══╧═════════╪════════╪═══════╪═════════╪═════════╪═══╪═══════╪═══════╝\n");
   printf("            │");
-  table_printf(nc, "│", "%*ss", PREFIXCOLUMNS, timebuf);
+  table_printf(nc, "│", "%*ss", PREFIXFMT(timebuf));
   table_printf(nc, "│", "%7lu", totalframes);
-  table_printf(nc, "│", "%*s", BPREFIXCOLUMNS, totalbuf);
-  table_printf(nc, "│", " %*ss", PREFIXCOLUMNS, rtimebuf);
+  table_printf(nc, "│", "%*s", BPREFIXFMT(totalbuf));
+  table_printf(nc, "│", " %*ss", PREFIXFMT(rtimebuf));
   table_printf(nc, "│", "%3ld", nsdelta ? totalrenderns * 100 / nsdelta : 0);
   table_printf(nc, "│", "%7.1f", nsdelta ? totalframes / ((double)nsdelta / GIG) : 0);
   printf("\n");