diff options
| -rw-r--r-- | text-motions.c | 77 | ||||
| -rw-r--r-- | text-motions.h | 4 |
2 files changed, 81 insertions, 0 deletions
diff --git a/text-motions.c b/text-motions.c index 6ca2f8f..04ccab1 100644 --- a/text-motions.c +++ b/text-motions.c @@ -15,6 +15,9 @@ */ #include <ctype.h> #include <string.h> +#include <stdlib.h> +#include <wchar.h> +#include <errno.h> #include "text-motions.h" #include "text-util.h" #include "util.h" @@ -218,6 +221,80 @@ int text_line_char_get(Text *txt, size_t pos) { return count; } +int text_line_width_get(Text *txt, size_t pos) { + int width = 0; + mbstate_t ps = { 0 }; + size_t bol = text_line_begin(txt, pos); + Iterator it = text_iterator_get(txt, bol); + + while (it.pos < pos) { + char buf[MB_CUR_MAX]; + size_t len = text_bytes_get(txt, it.pos, sizeof buf, buf); + if (len == 0 || buf[0] == '\r' || buf[0] == '\n') + break; + wchar_t wc; + size_t wclen = mbrtowc(&wc, buf, len, &ps); + if (wclen == (size_t)-1 && errno == EILSEQ) { + /* assume a replacement symbol will be displayed */ + width++; + } else if (wclen == (size_t)-2) { + /* do nothing, advance to next character */ + } else if (wclen == 0) { + /* assume NUL byte will be displayed as ^@ */ + width += 2; + } else if (buf[0] == '\t') { + width++; + } else { + int w = wcwidth(wc); + if (w == -1) + w = 2; /* assume non-printable will be displayed as ^{char} */ + width += w; + } + + if (!text_iterator_codepoint_next(&it, NULL)) + break; + } + + return width; +} + +size_t text_line_width_set(Text *txt, size_t pos, int width) { + int cur_width = 0; + mbstate_t ps = { 0 }; + size_t bol = text_line_begin(txt, pos); + Iterator it = text_iterator_get(txt, bol); + + for (;;) { + char buf[MB_CUR_MAX]; + size_t len = text_bytes_get(txt, it.pos, sizeof buf, buf); + if (len == 0 || buf[0] == '\r' || buf[0] == '\n') + break; + wchar_t wc; + size_t wclen = mbrtowc(&wc, buf, len, &ps); + if (wclen == (size_t)-1 && errno == EILSEQ) { + /* assume a replacement symbol will be displayed */ + cur_width++; + } else if (wclen == (size_t)-2) { + /* do nothing, advance to next character */ + } else if (wclen == 0) { + /* assume NUL byte will be displayed as ^@ */ + cur_width += 2; + } else if (buf[0] == '\t') { + cur_width++; + } else { + int w = wcwidth(wc); + if (w == -1) + w = 2; /* assume non-printable will be displayed as ^{char} */ + cur_width += w; + } + + if (cur_width >= width || !text_iterator_codepoint_next(&it, NULL)) + break; + } + + return it.pos; +} + size_t text_line_char_next(Text *txt, size_t pos) { char c; Iterator it = text_iterator_get(txt, pos); diff --git a/text-motions.h b/text-motions.h index cf108b3..dfe3acc 100644 --- a/text-motions.h +++ b/text-motions.h @@ -43,6 +43,10 @@ size_t text_line_offset(Text*, size_t pos, size_t off); int text_line_char_get(Text*, size_t pos); /* get position of the `count' grapheme in the line containing `pos' */ size_t text_line_char_set(Text*, size_t pos, int count); +/* get display width of line upto `pos' */ +int text_line_width_get(Text*, size_t pos); +/* get position of character being displayed at `width' in line containing `pos' */ +size_t text_line_width_set(Text*, size_t pos, int width); /* move to the next/previous grapheme on the same line */ size_t text_line_char_next(Text*, size_t pos); size_t text_line_char_prev(Text*, size_t pos); |