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authorMattias Andrée <maandree@kth.se>2021-04-01 23:39:01 +0200
committerMattias Andrée <maandree@kth.se>2021-04-01 23:39:01 +0200
commitc120520578692ee2448ba057e470ac580fc01de8 (patch)
treee1a89a37ff4abe4578edd50c5eff6411cdad3a9b /libterminput.c
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First commit
Signed-off-by: Mattias Andrée <maandree@kth.se>
Diffstat (limited to 'libterminput.c')
-rw-r--r--libterminput.c345
1 files changed, 345 insertions, 0 deletions
diff --git a/libterminput.c b/libterminput.c
new file mode 100644
index 0000000..a255373
--- /dev/null
+++ b/libterminput.c
@@ -0,0 +1,345 @@
+/* See LICENSE file for copyright and license details. */
+#include "libterminput.h"
+
+#include <alloca.h>
+#include <ctype.h>
+#include <limits.h>
+#include <string.h>
+#include <unistd.h>
+
+
+struct input {
+ enum libterminput_mod mods;
+ char symbol[7];
+};
+
+
+static int
+read_input(int fd, struct input *input, struct libterminput_state *ctx)
+{
+ unsigned char c, tc;
+ int r;
+
+ /* Get next byte from input */
+ if (ctx->have_stored) {
+ ctx->have_stored = 0;
+ c = (unsigned char)ctx->stored;
+ } else {
+ r = read(fd, &c, 1);
+ if (r <= 0)
+ return r;
+ }
+
+ if (ctx->n) {
+ /* Continuation of multibyte-character */
+ if ((c & 0xC0) != 0x80) {
+ /* Short multibyte-character: return short and store read byte from next input */
+ input->mods = ctx->mods;
+ ctx->partial[ctx->npartial] = '\0';
+ ctx->n = 0;
+ ctx->npartial = 0;
+ ctx->mods = 0;
+ ctx->have_stored = 1;
+ ctx->stored = (char)c;
+ strcpy(input->symbol, ctx->partial);
+ return 1;
+ } else {
+ /* Store byte, and if done, return */
+ ctx->partial[ctx->npartial++] = c;
+ if (ctx->npartial == ctx->n) {
+ ctx->partial[ctx->npartial] = '\0';
+ input->mods = ctx->mods;
+ ctx->npartial = 0;
+ ctx->mods = 0;
+ ctx->n = 0;
+ strcpy(input->symbol, ctx->partial);
+ return 1;
+ }
+ }
+ } else if (c == 033 && !*ctx->key) {
+ /* ESC at the beginning, save as a Meta/ESC */
+ ctx->meta += 1;
+ } else if (c == 0) {
+ /* CTRL on Space */
+ input->symbol[0] = ' ';
+ input->symbol[1] = '\0';
+ input->mods = ctx->mods | LIBTERMINPUT_CTRL;
+ ctx->mods = 0;
+ return 1;
+ } else if (c < (unsigned char)' ' && (char)c != '\t' && (char)c != '\b' && (char)c != '\n') {
+ /* CTRL on some some character key */
+ input->symbol[0] = (char)c + '@';
+ input->symbol[1] = '\0';
+ input->mods = ctx->mods | LIBTERMINPUT_CTRL;
+ ctx->mods = 0;
+ return 1;
+ } else if ((c & 0xC0) == 0xC0) {
+ /* Beginning of multibyte-character */
+ ctx->n = 0;
+ for (tc = c; tc & 0x80; tc <<= 1)
+ ctx->n++;
+ if (ctx->n > 6) {
+ /* If overlong, return first byte a single-byte-character */
+ input->symbol[0] = c;
+ input->symbol[1] = '\0';
+ input->mods = ctx->mods;
+ ctx->mods = 0;
+ return 1;
+ }
+ ctx->partial[0] = c;
+ ctx->npartial = 1;
+ } else {
+ /* Single-byte-character or stray multi-byte continuation byte */
+ input->symbol[0] = c;
+ input->symbol[1] = '\0';
+ input->mods = ctx->mods;
+ ctx->mods = 0;
+ return 1;
+ }
+
+ input->symbol[0] = '\0';
+ input->mods = -1;
+ return 1;
+}
+
+
+static void
+parse_sequence(union libterminput_input *input, struct libterminput_state *ctx)
+{
+ unsigned long long int *nums;
+ size_t keylen, n;
+ char *p;
+
+ /* Get number of numbers in the sequence, and allocate an array of at least 2 */
+ for (n = 2, p = ctx->key; *p; p++)
+ n += *p == ';';
+ nums = alloca(n * sizeof(*nums));
+ nums[0] = nums[1] = 0;
+
+ /* Read numbers and remove numbers and delimiters */
+ for (keylen = 0, n = 0, p = ctx->key; *p; p++) {
+ if (*p == ';') {
+ nums[++n] = 0; /* We made sure above to allocate one extra */
+ } else if (!isdigit(*p)) {
+ ctx->key[keylen++] = *p;
+ } else if (n < 3) {
+ if (nums[n] < (ULLONG_MAX - (*p & 15)) / 10)
+ nums[n] = nums[n] * 10 + (*p & 15);
+ else
+ nums[n] = ULLONG_MAX;
+ }
+ }
+ ctx->key[keylen] = '\0';
+
+ /* Get times and mods, and reset symbol, and more as keypress */
+ input->type = LIBTERMINPUT_KEYPRESS;
+ input->keypress.symbol[0] = '\0';
+ input->keypress.times = nums[0] + !nums[0];
+ input->keypress.mods = nums[1] > 1 ? nums[1] - 1 : 0;
+ input->keypress.mods |= ctx->meta > 1 ? LIBTERMINPUT_META : 0;
+
+ switch (ctx->key[0]) {
+ case '[':
+ switch (keylen) {
+ case 2:
+ switch (ctx->key[1]) {
+ case 'A': input->keypress.key = LIBTERMINPUT_UP; break;
+ case 'B': input->keypress.key = LIBTERMINPUT_DOWN; break;
+ case 'C': input->keypress.key = LIBTERMINPUT_RIGHT; break;
+ case 'D': input->keypress.key = LIBTERMINPUT_LEFT; break;
+ case 'E': input->keypress.key = LIBTERMINPUT_BEGIN; break;
+ case 'G': input->keypress.key = LIBTERMINPUT_BEGIN; break;
+ case 'P': input->keypress.key = LIBTERMINPUT_PAUSE; break;
+ case 'Z':
+ input->keypress.key = LIBTERMINPUT_TAB;
+ input->keypress.mods |= LIBTERMINPUT_SHIFT;
+ break;
+ case '~':
+ input->keypress.times = 1;
+ switch (nums[0]) {
+ case 1: input->keypress.key = LIBTERMINPUT_HOME; break;
+ case 2: input->keypress.key = LIBTERMINPUT_INS; break;
+ case 3: input->keypress.key = LIBTERMINPUT_DEL; break;
+ case 4: input->keypress.key = LIBTERMINPUT_END; break;
+ case 5: input->keypress.key = LIBTERMINPUT_PRIOR; break;
+ case 6: input->keypress.key = LIBTERMINPUT_NEXT; break;
+ case 15: input->keypress.key = LIBTERMINPUT_F5; break;
+ case 17: input->keypress.key = LIBTERMINPUT_F6; break;
+ case 18: input->keypress.key = LIBTERMINPUT_F7; break;
+ case 19: input->keypress.key = LIBTERMINPUT_F8; break;
+ case 20: input->keypress.key = LIBTERMINPUT_F9; break;
+ case 21: input->keypress.key = LIBTERMINPUT_F10; break;
+ case 23: input->keypress.key = LIBTERMINPUT_F11; break;
+ case 24: input->keypress.key = LIBTERMINPUT_F12; break;
+ case 25: input->keypress.key = LIBTERMINPUT_F1; break;
+ case 26: input->keypress.key = LIBTERMINPUT_F2; break;
+ case 28: input->keypress.key = LIBTERMINPUT_F3; break;
+ case 29: input->keypress.key = LIBTERMINPUT_F4; break;
+ case 31: input->keypress.key = LIBTERMINPUT_F5; break;
+ case 32: input->keypress.key = LIBTERMINPUT_F6; break;
+ case 33: input->keypress.key = LIBTERMINPUT_F7; break;
+ case 34: input->keypress.key = LIBTERMINPUT_F8; break;
+ default:
+ input->type = LIBTERMINPUT_NONE;
+ return;
+ }
+ if (25 <= nums[0] && nums[0] <= 34)
+ input->keypress.mods |= LIBTERMINPUT_SHIFT;
+ break;
+ default:
+ input->type = LIBTERMINPUT_NONE;
+ break;
+ }
+ break;
+ case 3:
+ switch (ctx->key[1] == '[' ? ctx->key[2] : 0) {
+ case 'A': input->keypress.key = LIBTERMINPUT_F1; break;
+ case 'B': input->keypress.key = LIBTERMINPUT_F2; break;
+ case 'C': input->keypress.key = LIBTERMINPUT_F3; break;
+ case 'D': input->keypress.key = LIBTERMINPUT_F4; break;
+ case 'E': input->keypress.key = LIBTERMINPUT_F5; break;
+ default:
+ input->type = LIBTERMINPUT_NONE;
+ break;
+ }
+ break;
+ default:
+ input->type = LIBTERMINPUT_NONE;
+ break;
+ }
+ break;
+
+ case 'O':
+ switch (!ctx->key[2] ? ctx->key[1] : 0) {
+ case 'H': input->keypress.key = LIBTERMINPUT_HOME; break;
+ case 'F': input->keypress.key = LIBTERMINPUT_END; break;
+ case 'P': input->keypress.key = LIBTERMINPUT_F1; break;
+ case 'Q': input->keypress.key = LIBTERMINPUT_F2; break;
+ case 'R': input->keypress.key = LIBTERMINPUT_F3; break;
+ case 'S': input->keypress.key = LIBTERMINPUT_F4; break;
+ case 'p': input->keypress.key = LIBTERMINPUT_KEYPAD_0; break;
+ case 'q': input->keypress.key = LIBTERMINPUT_KEYPAD_1; break;
+ case 'r': input->keypress.key = LIBTERMINPUT_KEYPAD_2; break;
+ case 's': input->keypress.key = LIBTERMINPUT_KEYPAD_3; break;
+ case 't': input->keypress.key = LIBTERMINPUT_KEYPAD_4; break;
+ case 'u': input->keypress.key = LIBTERMINPUT_KEYPAD_5; break;
+ case 'v': input->keypress.key = LIBTERMINPUT_KEYPAD_6; break;
+ case 'w': input->keypress.key = LIBTERMINPUT_KEYPAD_7; break;
+ case 'x': input->keypress.key = LIBTERMINPUT_KEYPAD_8; break;
+ case 'y': input->keypress.key = LIBTERMINPUT_KEYPAD_9; break;
+ case 'm': input->keypress.key = LIBTERMINPUT_KEYPAD_MINUS; break;
+ case 'l': input->keypress.key = LIBTERMINPUT_KEYPAD_COMMA; break;
+ case 'b': input->keypress.key = LIBTERMINPUT_KEYPAD_POINT; break;
+ case 'M': input->keypress.key = LIBTERMINPUT_KEYPAD_ENTER; break;
+ default:
+ input->type = LIBTERMINPUT_NONE;
+ break;
+ }
+ break;
+
+ default:
+ /* This shouldn't happen */
+ input->type = LIBTERMINPUT_NONE;
+ break;
+ }
+}
+
+
+int
+libterminput_read(int fd, union libterminput_input *input, struct libterminput_state *ctx)
+{
+ struct input ret;
+ size_t n, m;
+ char *p;
+ int r;
+
+ if (!ctx->inited) {
+ ctx->inited = 1;
+ memset(input, 0, sizeof(*input));
+ } else if (input->type == LIBTERMINPUT_KEYPRESS && input->keypress.times > 1) {
+ input->keypress.times -= 1;
+ return 1;
+ }
+
+ r = read_input(fd, &ret, ctx);
+ if (r <= 0)
+ return r;
+
+again:
+ if (!*ret.symbol) {
+ /* Incomplete input */
+ if (ctx->meta < 3) {
+ /* Up to two Meta/ESC, wait until a third or something else is read */
+ input->type = LIBTERMINPUT_NONE;
+ return 1;
+ }
+ /* Three ESC's */
+ input->type = LIBTERMINPUT_KEYPRESS;
+ input->keypress.key = LIBTERMINPUT_ESC;
+ input->keypress.times = 3;
+ input->keypress.mods = ret.mods;
+ input->keypress.symbol[0] = '\0';
+ ctx->meta -= 3;
+ } else if (*ctx->key) {
+ /* Special keys */
+ if (ret.mods) {
+ /* Special key was aborted, restart */
+ *ctx->key = '\0';
+ goto again;
+ }
+ /* Add new input to sequence */
+ n = strlen(ctx->key);
+ m = strlen(ret.symbol);
+ if (n + m >= sizeof(ctx->key)) {
+ /* Abort if too long */
+ input->type = LIBTERMINPUT_NONE;
+ return 1;
+ }
+ p = stpcpy(&ctx->key[n], ret.symbol);
+ /* Check if sequence is complete */
+ if (!isalpha(p[-1]) && p[-1] != '~') {
+ input->type = LIBTERMINPUT_NONE;
+ return 1;
+ }
+ /* Parse the complete sequence */
+ parse_sequence(input, ctx);
+ /* Reset */
+ ctx->meta = 0;
+ ctx->key[0] = '\0';
+ } else if (ctx->meta && (!strcmp(ret.symbol, "[") || !strcmp(ret.symbol, "O"))) {
+ /* ESC [ or ESC 0 is used as the beginning of most special keys */
+ strcpy(ctx->key, ret.symbol);
+ input->type == LIBTERMINPUT_NONE;
+ } else {
+ /* Character input and single-byte special keys */
+ input->type = LIBTERMINPUT_KEYPRESS;
+ input->keypress.mods = ret.mods;
+ input->keypress.times = 1;
+ if (ctx->meta) {
+ /* Transfer meta modifier from state to input */
+ input->keypress.mods |= LIBTERMINPUT_META;
+ ctx->meta = 0;
+ }
+ switch (ret.symbol[1] ? 0 : ret.symbol[0]) {
+ case 127:
+ case '\b':
+ input->keypress.key = LIBTERMINPUT_ERASE;
+ input->keypress.symbol[0] = '\0';
+ break;
+ case '\t':
+ input->keypress.key = LIBTERMINPUT_TAB;
+ input->keypress.symbol[0] = '\0';
+ break;
+ case '\n':
+ input->keypress.key = LIBTERMINPUT_ENTER;
+ input->keypress.symbol[0] = '\0';
+ break;
+ default:
+ input->keypress.key = LIBTERMINPUT_SYMBOL;
+ strcpy(input->keypress.symbol, ret.symbol);
+ break;
+ }
+ }
+
+ return 1;
+}