From b76a53fe624831533f8d9d3090e09ce18fb13612 Mon Sep 17 00:00:00 2001 From: Michael Jumper Date: Sat, 21 Jul 2012 10:00:00 -0700 Subject: [PATCH] Walk element content to determine character length (NOTE: need to save state between walks to avoid rewalking old characters and turning a linear-time parse into quadratic-time). --- libguac/src/protocol.c | 31 +++++++++++++++++++++++++------ 1 file changed, 25 insertions(+), 6 deletions(-) diff --git a/libguac/src/protocol.c b/libguac/src/protocol.c index 0ace2ac6..c0c93034 100644 --- a/libguac/src/protocol.c +++ b/libguac/src/protocol.c @@ -412,9 +412,15 @@ guac_instruction* guac_protocol_read_instruction(guac_socket* socket, /* Loop until a instruction is read */ for (;;) { - /* Length of element */ + /* Length of element, in Unicode characters */ int element_length = 0; + /* Length of element, in bytes */ + int element_byte_length = 0; + + /* Current position within the element, in Unicode characters */ + int current_unicode_length = 0; + /* Position within buffer */ int i = socket->__instructionbuf_parse_start; @@ -431,21 +437,34 @@ guac_instruction* guac_protocol_read_instruction(guac_socket* socket, /* Otherwise, if end of length */ else if (c == '.') { + /* Calculate element byte length by walking buffer */ + while (i + element_byte_length < + socket->__instructionbuf_used_length) { + + /* Get next byte */ + c = socket->__instructionbuf[i + element_byte_length]; + + /* Update byte and character lengths */ + element_byte_length += guac_utf8_charsize((unsigned) c); + current_unicode_length++; + + } + /* Verify element is fully read */ - if (i + element_length < socket->__instructionbuf_used_length) { + if (current_unicode_length == element_length) { /* Get element value */ char* elementv = &(socket->__instructionbuf[i]); /* Get terminator, set null terminator of elementv */ - char terminator = elementv[element_length]; - elementv[element_length] = '\0'; + char terminator = elementv[element_byte_length]; + elementv[element_byte_length] = '\0'; /* Move to char after terminator of element */ - i += element_length+1; + i += element_byte_length+1; /* Reset element length */ - element_length = 0; + element_length = element_byte_length = 0; /* As element has been read successfully, update * parse start */