support extended ASCII characters

Author: paigeruten

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## 1.0.0beta2 (April 6, 2017)
+
+* Replace all instances of `isprint()` with `!iscntrl()`, so that extended
+  ASCII characters can be inserted and displayed in the editor.
+* Include font files in offline version of tutorial.
+
 ## 1.0.0beta1 (April 6, 2017)
 
 * Add changelog.

doc/02.enteringRawMode.md

@@ -138,11 +138,13 @@ the character it represents if it is a printable character.
 
 {{keypresses}}
 
-`isprint()` comes from `<ctype.h>`, and `printf()` comes from `<stdio.h>`.
+`iscntrl()` comes from `<ctype.h>`, and `printf()` comes from `<stdio.h>`.
 
-`isprint()` tests whether a character is printable. Letters, digits, symbols,
-punctuation, and spaces are all printable. Control characters, newlines, tabs,
-and the null byte are all considered nonprintable.
+`iscntrl()` tests whether a character is a control character. Control
+characters are nonprintable characters that we don't want to print to the
+screen. ASCII codes 0&ndash;31 are all control characters, and 127 is also a
+control character. ASCII codes 32&ndash;126 are all printable. (Check out the
+[ASCII table](http://asciitable.com) to see all of the characters.)
 
 `printf()` can print multiple representations of a byte. `%d` tells it to
 format the byte as a decimal number (its ASCII code), and `%c` tells it to
@@ -311,8 +313,7 @@ As far as I can tell:
 * `INPCK` enables parity checking, which doesn't seem to apply to modern
   terminal emulators.
 * `ISTRIP` causes the 8th bit of each input byte to be stripped, meaning it
-  will set it to `0`. I don't know of any keys that send bytes with the 8th
-  bit set anyways.
+  will set it to `0`. This is probably already turned off.
 * `CS8` is not a flag, it is a bit mask with multiple bits, which we set using
   the bitwise-OR (`|`) operator unlike all the flags we are turning off. It
   sets the character size (CS) to 8 bits per byte. On my system, it's already

doc/07.syntaxHighlighting.md

@@ -488,12 +488,10 @@ counterparts, we'll render them using inverted colors (black on white).
 
 {{nonprintables}}
 
-We use `isprint()` to check if the current character is printable. If not, we
-translate it into a printable character by adding its value to `'@'` (in ASCII,
-the capital letters of the alphabet come after the `@` character), or using the
-`'?'` character if it's not in the alphabetic range. Notice that we have to
-make sure it's greater than or equal to `0`, because `char` values can be
-negative (which they often will be when opening a binary file).
+We use `iscntrl()` to check if the current character is a control character. If
+so, we translate it into a printable character by adding its value to `'@'` (in
+ASCII, the capital letters of the alphabet come after the `@` character), or
+using the `'?'` character if it's not in the alphabetic range.
 
 We then use the `<esc>[7m` escape sequence to switch to inverted colors before
 printing the translated symbol. We use `<esc>[m` to turn off inverted colors

doc/08.appendices.md

@@ -158,11 +158,6 @@ program called [leg](https://github.com/yjerem/leg). I will try to document the
 process of editing the `steps.diff` file using `leg` in that repo's `README.md`
 file, soon.
 
-Changes to the code will cause problems for everyone who is currently part of
-the way through the tutorial, so these changes should probably be kept in a
-separate branch until a new, `1.0.0` version of the tutorial is released or
-something. Changes to the code should be bugfixes only, not new features.
-
 To use `leg` to generate the final static HTML files:
 
 1. You need to have Ruby installed.

leg.yml

@@ -1,6 +1,6 @@
 ---
 :name: kilo
-:version: "1.0.0beta1"
+:version: "1.0.0beta2"
 :title: Build Your Own Text Editor
 :rouge_theme: github
 :bold_weight: 500

steps.diff

@@ -125,10 +125,10 @@ diff --git a/kilo.c b/kilo.c
    char c;
 -  while (read(STDIN_FILENO, &c, 1) == 1 && c != 'q');
 +  while (read(STDIN_FILENO, &c, 1) == 1 && c != 'q') {
-+    if (isprint(c)) {
-+      printf("%d ('%c')\n", c, c);
-+    } else {
++    if (iscntrl(c)) {
 +      printf("%d\n", c);
++    } else {
++      printf("%d ('%c')\n", c, c);
 +    }
 +  }
 +
@@ -210,12 +210,12 @@ diff --git a/kilo.c b/kilo.c
 @@ -28,9 +28,9 @@ int main() {
    char c;
    while (read(STDIN_FILENO, &c, 1) == 1 && c != 'q') {
-     if (isprint(c)) {
--      printf("%d ('%c')\n", c, c);
-+      printf("%d ('%c')\r\n", c, c);
-     } else {
+     if (iscntrl(c)) {
 -      printf("%d\n", c);
 +      printf("%d\r\n", c);
+     } else {
+-      printf("%d ('%c')\n", c, c);
++      printf("%d ('%c')\r\n", c, c);
      }
    }
 
@@ -258,10 +258,10 @@ diff --git a/kilo.c b/kilo.c
 +  while (1) {
 +    char c = '\0';
 +    read(STDIN_FILENO, &c, 1);
-     if (isprint(c)) {
-       printf("%d ('%c')\r\n", c, c);
-     } else {
+     if (iscntrl(c)) {
        printf("%d\r\n", c);
+     } else {
+       printf("%d ('%c')\r\n", c, c);
      }
 +    if (c == 'q') break;
    }
@@ -325,8 +325,8 @@ diff --git a/kilo.c b/kilo.c
      char c = '\0';
 -    read(STDIN_FILENO, &c, 1);
 +    if (read(STDIN_FILENO, &c, 1) == -1 && errno != EAGAIN) die("read");
-     if (isprint(c)) {
-       printf("%d ('%c')\r\n", c, c);
+     if (iscntrl(c)) {
+       printf("%d\r\n", c);
      } else {
 
 ~~~ step: sections c1
@@ -381,10 +381,10 @@ diff --git a/kilo.c b/kilo.c
    while (1) {
      char c = '\0';
      if (read(STDIN_FILENO, &c, 1) == -1 && errno != EAGAIN) die("read");
--    if (isprint(c)) {
--      printf("%d ('%c')\r\n", c, c);
--    } else {
+-    if (iscntrl(c)) {
 -      printf("%d\r\n", c);
+-    } else {
+-      printf("%d ('%c')\r\n", c, c);
 -    }
 -    if (c == 'q') break;
 +    if (c == CTRL_KEY('q')) break;
@@ -665,10 +665,10 @@ diff --git a/kilo.c b/kilo.c
 +  printf("\r\n");
 +  char c;
 +  while (read(STDIN_FILENO, &c, 1) == 1) {
-+    if (isprint(c)) {
-+      printf("%d ('%c')\r\n", c, c);
-+    } else {
++    if (iscntrl(c)) {
 +      printf("%d\r\n", c);
++    } else {
++      printf("%d ('%c')\r\n", c, c);
 +    }
 +  }
 +
@@ -705,10 +705,10 @@ diff --git a/kilo.c b/kilo.c
 -  printf("\r\n");
 -  char c;
 -  while (read(STDIN_FILENO, &c, 1) == 1) {
--    if (isprint(c)) {
--      printf("%d ('%c')\r\n", c, c);
--    } else {
+-    if (iscntrl(c)) {
 -      printf("%d\r\n", c);
+-    } else {
+-      printf("%d ('%c')\r\n", c, c);
 -    }
 +  while (i < sizeof(buf) - 1) {
 +    if (read(STDIN_FILENO, &buf[i], 1) != 1) break;
@@ -3106,7 +3106,7 @@ diff --git a/kilo.c b/kilo.c
 +        editorSetStatusMessage("");
 +        return buf;
 +      }
-+    } else if (isprint(c)) {
++    } else if (!iscntrl(c)) {
 +      if (buflen == bufsize - 1) {
 +        bufsize *= 2;
 +        buf = realloc(buf, bufsize);
@@ -3330,7 +3330,7 @@ diff --git a/kilo.c b/kilo.c
 +        if (callback) callback(buf, c);
          return buf;
        }
-     } else if (isprint(c)) {
+     } else if (!iscntrl(c)) {
 @@ -594,6 +596,8 @@ char *editorPrompt(char *prompt) {
        buf[buflen++] = c;
        buf[buflen] = '\0';
@@ -4301,8 +4301,8 @@ diff --git a/kilo.c b/kilo.c
        int j;
        for (j = 0; j < len; j++) {
 -        if (hl[j] == HL_NORMAL) {
-+        if (!isprint(c[j])) {
-+          char sym = (c[j] >= 0 && c[j] <= 26) ? '@' + c[j] : '?';
++        if (iscntrl(c[j])) {
++          char sym = (c[j] <= 26) ? '@' + c[j] : '?';
 +          abAppend(ab, "\x1b[7m", 4);
 +          abAppend(ab, &sym, 1);
 +          abAppend(ab, "\x1b[m", 3);