column: fix unaligned cols in text with ansi escapes

diff --git a/text-utils/column.c b/text-utils/column.c
index 06aeaa08a806a90a03eec6b02a7b443b9297d595..1af7c76b6cbe4eab742c50d3e105145b4bd298d2 100644 (file)
--- a/text-utils/column.c
+++ b/text-utils/column.c
@@ -104,21 +104,89 @@ struct column_control {
                     tab_noheadings :1;
 };
 
+typedef enum {
+       ANSI_CHR = 'A',
+       ANSI_ESC = '\x1b',
+       ANSI_SGR = '[',
+       ANSI_OSC = ']',
+       ANSI_APC = '_',
+       ANSI_BSL = '\\'
+} ansi_csi_sgr;
+
+static size_t ansi_esc_width(ansi_csi_sgr *state, size_t *found, const wchar_t *str) {
+       switch (*state) {
+       case ANSI_CHR:
+               // Begins Ansi escape sequence with ESC ( written as \x5b \033 or ^[ )
+               if (*str == '\x1b')
+                       *state = ANSI_ESC;
+               return 0;
+       case ANSI_ESC:
+               // Ansi Fe escape sequences allows the range \x40 to \x5f
+               switch (*str) {
+               case '[':
+                       *state = ANSI_SGR;
+                       break;
+               case ']':
+                       *state = ANSI_OSC;
+                       break;
+               case '_':
+               case 'P':
+               case '^':
+                       *state = ANSI_APC;
+                       break;
+               default:
+                       *state = ANSI_CHR;
+                       return 0;
+               }
+               *found = 1;
+               return 0;
+       case ANSI_SGR:
+               // Fe allows the range \x30-\x3f but SGR only uses: 0-9 ';' ':'
+               *found += 1;
+               if (*str >= '0' && *str <= '?')
+                       return 0;
+               // Fe Ends on the range \x40-\x7e but SGR ends on 'm'
+               if (*str <= '@' && *str >= '~')
+                       *found = 0;
+               break;
+       case ANSI_APC:
+       case ANSI_OSC:
+               *found += 1;
+               if (*str == '\x9c' || *str == '\x7') // Ends on ST or BEL
+                       break;
+               else if (*str == '\x1b') // Ends on ESC BACKSLASH
+                       *state = ANSI_BSL;
+               return 0;
+       case ANSI_BSL:
+               if (*str == '\x5c')
+                       break;
+               *found = 0;
+               return 0;
+       }
+       size_t res = *found;
+       *state = ANSI_CHR;
+       *found = 0;
+       return res;
+}
+
 static size_t width(const wchar_t *str)
 {
-       size_t width = 0;
+       size_t count = 0;
+       size_t found = 0;
+       ansi_csi_sgr state = ANSI_CHR;
 
        for (; *str != '\0'; str++) {
 #ifdef HAVE_WIDECHAR
                int x = wcwidth(*str);  /* don't use wcswidth(), need to ignore non-printable */
                if (x > 0)
-                       width += x;
+                       count += x;
 #else
                if (isprint(*str))
-                       width++;
+                       count++;
 #endif
+               count -= ansi_esc_width(&state, &found, str);
        }
-       return width;
+       return count;
 }
 
 static wchar_t *mbs_to_wcs(const char *s)