diff options
| -rw-r--r-- | editors/vi.c | 119 |
1 files changed, 58 insertions, 61 deletions
diff --git a/editors/vi.c b/editors/vi.c index 02bdbb37b..6902b7688 100644 --- a/editors/vi.c +++ b/editors/vi.c @@ -210,11 +210,7 @@ struct globals { #endif // Should be just enough to hold a key sequence, // but CRASME mode uses it as generated command buffer too -#if ENABLE_FEATURE_VI_CRASHME - char readbuffer[128]; -#else - char readbuffer[32]; -#endif + char readbuffer[8]; #define STATUS_BUFFER_LEN 200 char status_buffer[STATUS_BUFFER_LEN]; // messages to the user #if ENABLE_FEATURE_VI_DOT_CMD @@ -2201,18 +2197,23 @@ static char readit(void) // read (maybe cursor) key from stdin { char c; int n; - struct esc_cmds { + + // Known escape sequences for cursor and function keys. + static const struct esc_cmds { const char seq[4]; char val; - }; - - static const struct esc_cmds esccmds[] = { + } esccmds[] = { {"OA" , VI_K_UP }, // cursor key Up {"OB" , VI_K_DOWN }, // cursor key Down {"OC" , VI_K_RIGHT }, // Cursor Key Right {"OD" , VI_K_LEFT }, // cursor key Left {"OH" , VI_K_HOME }, // Cursor Key Home {"OF" , VI_K_END }, // Cursor Key End + {"OP" , VI_K_FUN1 }, // Function Key F1 + {"OQ" , VI_K_FUN2 }, // Function Key F2 + {"OR" , VI_K_FUN3 }, // Function Key F3 + {"OS" , VI_K_FUN4 }, // Function Key F4 + {"[A" , VI_K_UP }, // cursor key Up {"[B" , VI_K_DOWN }, // cursor key Down {"[C" , VI_K_RIGHT }, // Cursor Key Right @@ -2225,10 +2226,6 @@ static char readit(void) // read (maybe cursor) key from stdin {"[4~" , VI_K_END }, // Cursor Key End {"[5~" , VI_K_PAGEUP }, // Cursor Key Page Up {"[6~" , VI_K_PAGEDOWN}, // Cursor Key Page Down - {"OP" , VI_K_FUN1 }, // Function Key F1 - {"OQ" , VI_K_FUN2 }, // Function Key F2 - {"OR" , VI_K_FUN3 }, // Function Key F3 - {"OS" , VI_K_FUN4 }, // Function Key F4 // careful: these have no terminating NUL! {"[11~", VI_K_FUN1 }, // Function Key F1 {"[12~", VI_K_FUN2 }, // Function Key F2 @@ -2243,67 +2240,67 @@ static char readit(void) // read (maybe cursor) key from stdin {"[23~", VI_K_FUN11 }, // Function Key F11 {"[24~", VI_K_FUN12 }, // Function Key F12 }; - enum { ESCCMDS_COUNT = ARRAY_SIZE(esccmds) }; fflush(stdout); + + // If no data, block waiting for input. n = chars_to_parse; - // get input from User - are there already input chars in Q? - if (n <= 0) { - // the Q is empty, wait for a typed char - again: - n = safe_read(STDIN_FILENO, readbuffer, sizeof(readbuffer)); + while (!n) { + n = safe_read(0, readbuffer, 1); if (n <= 0) { place_cursor(rows - 1, 0, FALSE); // go to bottom of screen clear_to_eol(); // erase to end of line cookmode(); // terminal to "cooked" bb_error_msg_and_die("can't read user input"); } - /* elsewhere we can get very confused by NULs */ - if (readbuffer[0] == '\0') - goto again; - if (readbuffer[0] == 27) { - // This is an ESC char. Is this Esc sequence? - // Could be bare Esc key. See if there are any - // more chars to read after the ESC. This would - // be a Function or Cursor Key sequence. - struct pollfd pfd[1]; - pfd[0].fd = 0; - pfd[0].events = POLLIN; - // keep reading while there are input chars, and room in buffer - // for a complete ESC sequence (assuming 8 chars is enough) - while ((safe_poll(pfd, 1, 0) > 0) - && ((size_t)n <= (sizeof(readbuffer) - 8)) - ) { - // read the rest of the ESC string - int r = safe_read(STDIN_FILENO, readbuffer + n, sizeof(readbuffer) - n); - if (r > 0) - n += r; + // Returning NUL from this routine would be bad. + if (*readbuffer) break; + } + + // Grab character to return from buffer + c = *readbuffer; + n--; + if (n) memmove(readbuffer, readbuffer+1, n); + + // If it's an escape sequence, loop through known matches. + if (c == 27) { + const struct esc_cmds *eindex; + + for (eindex = esccmds; eindex < esccmds+ARRAY_SIZE(esccmds); eindex++) { + int i=0, cnt = strnlen(eindex->seq, 4); + + // Loop through chars in this sequence. + for (;;) { + + // If we've matched this escape sequence so far but need more + // chars, read another as long as it wouldn't block. (Note that + // escape sequences come in as a unit, so if we would block + // it's not really an escape sequence.) + if (n <= i) { + struct pollfd pfd; + pfd.fd = 0; + pfd.events = POLLIN; + if (0 < safe_poll(&pfd, 1, 0) + && 0 < safe_read(0, readbuffer + n, 1)) + n++; + + // Since the array is sorted from shortest to longest, if + // we needed more data we can't match anything later, so + // break out of both loops. + else goto loop_out; + } + if (readbuffer[i] != eindex->seq[i]) break; + if (++i == cnt) { + c = eindex->val; + n = 0; + goto loop_out; + } } } - chars_to_parse = n; } - c = readbuffer[0]; - if (c == 27 && n > 1) { - // Maybe cursor or function key? - const struct esc_cmds *eindex; +loop_out: - for (eindex = esccmds; eindex < &esccmds[ESCCMDS_COUNT]; eindex++) { - int cnt = strnlen(eindex->seq, 4); - if (n <= cnt) - continue; - if (strncmp(eindex->seq, readbuffer + 1, cnt) != 0) - continue; - c = eindex->val; // magic char value - n = cnt + 1; // squeeze out the ESC sequence - goto found; - } - // defined ESC sequence not found - } - n = 1; - found: - // remove key sequence from Q - chars_to_parse -= n; - memmove(readbuffer, readbuffer + n, sizeof(readbuffer) - n); + chars_to_parse = n; return c; } |