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Diffstat (limited to 'nuttx/graphics/nxconsole/nxcon_vt100.c')
-rw-r--r-- | nuttx/graphics/nxconsole/nxcon_vt100.c | 289 |
1 files changed, 289 insertions, 0 deletions
diff --git a/nuttx/graphics/nxconsole/nxcon_vt100.c b/nuttx/graphics/nxconsole/nxcon_vt100.c new file mode 100644 index 000000000..3e3374dce --- /dev/null +++ b/nuttx/graphics/nxconsole/nxcon_vt100.c @@ -0,0 +1,289 @@ +/**************************************************************************** + * nuttx/graphics/nxconsole/nxcon_vt100.c + * + * Copyright (C) 2012 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <gnutt@nuttx.org> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name NuttX nor the names of its contributors may be + * used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> + +#include <string.h> +#include <assert.h> + +#include <nuttx/vt100.h> + +#include "nxcon_internal.h" + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Types + ****************************************************************************/ + +typedef int (*seqhandler_t)(FAR struct nxcon_state_s *priv); + +struct vt100_sequence_s +{ + FAR const char *seq; + seqhandler_t handler; + uint8_t size; +}; + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +static int nxcon_erasetoeol(FAR struct nxcon_state_s *priv); + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +/* All recognized VT100 escape sequences. Very little as present, this is + * a placeholder for a future, more complete VT100 emulation. + */ + +/* <esc>[K is the VT100 command erases to the end of the line. */ + +static const char g_erasetoeol[] = VT100_CLEAREOL; + +/* The list of all VT100 sequences supported by the emulation */ + +static const struct vt100_sequence_s g_vt100sequences[] = +{ + {g_erasetoeol, nxcon_erasetoeol, sizeof(g_erasetoeol)}, + {NULL, NULL, 0} +}; + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: nxcon_erasetoeol + * + * Description: + * Handle the erase-to-eol VT100 escapte sequence + * + * Input Parameters: + * priv - Driver data structure + * + * Returned Value: + * The index of the match in g_vt100sequences[] + * + ****************************************************************************/ + +static int nxcon_erasetoeol(FAR struct nxcon_state_s *priv) +{ + /* Does nothing yet (other than consume the sequence) */ + + return OK; +} + +/**************************************************************************** + * Name: nxcon_vt100part + * + * Description: + * Return the next entry that is a partial match to the sequence. + * + * Input Parameters: + * priv - Driver data structure + * seqsize - The number of bytes in the sequence + * startndx - The index to start searching + * + * Returned Value: + * A pointer to the matching sequence in g_vt100sequences[] + * + ****************************************************************************/ + +FAR const struct vt100_sequence_s * +nxcon_vt100part(FAR struct nxcon_state_s *priv, int seqsize) +{ + FAR const struct vt100_sequence_s *seq; + int ndx; + + /* Search from the beginning of the sequence table */ + + for (ndx = 0; g_vt100sequences[ndx].seq; ndx++) + { + /* Is this sequence big enough? */ + + seq = &g_vt100sequences[ndx]; + if (seq->size >= seqsize) + { + /* Yes... are the first 'seqsize' bytes the same */ + + if (memcmp(seq->seq, priv->seq, seqsize) == 0) + { + /* Yes.. return the match */ + + return seq; + } + } + } + return NULL; +} + +/**************************************************************************** + * Name: nxcon_vt100seq + * + * Description: + * Determine if the new sequence is a part of a supported VT100 escape + * sequence. + * + * Input Parameters: + * priv - Driver data structure + * seqsize - The number of bytes in the sequence + * + * Returned Value: + * state - See enum nxcon_vt100state_e; + * + ****************************************************************************/ + +static enum nxcon_vt100state_e nxcon_vt100seq(FAR struct nxcon_state_s *priv, + int seqsize) +{ + FAR const struct vt100_sequence_s *seq; + enum nxcon_vt100state_e ret; + + /* Is there any VT100 escape sequence that matches what we have + * buffered so far? + */ + + seq = nxcon_vt100part(priv, seqsize); + if (seq) + { + /* Yes.. if the size of that escape sequence is the same as what we + * have buffered, then we have an exact match. + */ + + if (seq->size == seqsize) + { + /* Process the VT100 sequence */ + + seq->handler(priv); + priv->nseq = 0; + return VT100_PROCESSED; + } + + /* The 'seqsize' is still smaller than the potential match(es). We + * will need to collect more characters before we can make a decision. + * Retun an indication that we have consumed the character. + */ + + return VT100_CONSUMED; + } + + /* We get here on a failure. The buffer sequence is not part of any + * supported VT100 escape sequence. If seqsize > 1 then we need to + * return a special value because we have to re-process the buffered + * data. + */ + + ret = seqsize > 1 ? VT100_ABORT : VT100_NOT_CONSUMED; + return ret; +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: nxcon_vt100 + * + * Description: + * Test if the newly received byte is part of a VT100 escape sequence + * + * Input Parameters: + * priv - Driver data structure + * ch - The newly received character + * + * Returned Value: + * state - See enum nxcon_vt100state_e; + * + ****************************************************************************/ + +enum nxcon_vt100state_e nxcon_vt100(FAR struct nxcon_state_s *priv, char ch) +{ + enum nxcon_vt100state_e ret; + int seqsize; + + DEBUGASSERT(priv && priv->nseq < VT100_MAX_SEQUENCE); + + /* If we have no buffered characters, then 'ch' must be the first character + * of an escape sequence. + */ + + if (priv->nseq < 1) + { + /* The first character of an escape sequence must be an an escape + * character (duh). + */ + + if (ch != ASCII_ESC) + { + return VT100_NOT_CONSUMED; + } + + /* Add the escape character to the buffer but don't bother with any + * further checking. + */ + + priv->seq[0] = ASCII_ESC; + priv->nseq = 1; + return VT100_CONSUMED; + } + + /* Temporarily add the next character to the buffer */ + + seqsize = priv->nseq; + priv->seq[seqsize] = ch; + + /* Then check if this sequence is part of an a valid escape sequence */ + + seqsize++; + ret = nxcon_vt100seq(priv, seqsize); + if (ret == VT100_CONSUMED) + { + /* The newly added character is indeed part of a VT100 escape sequence + * (which is still incomplete). Keep it in the buffer. + */ + + priv->nseq = seqsize; + } + return ret; +} |