diff options
Diffstat (limited to 'client/readline.cc')
| -rw-r--r-- | client/readline.cc | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/client/readline.cc b/client/readline.cc new file mode 100644 index 00000000000..95e98cb90c2 --- /dev/null +++ b/client/readline.cc @@ -0,0 +1,216 @@ +/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with this library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, + MA 02111-1307, USA */ + +/* readline for batch mode */ + +#include <global.h> +#include <my_sys.h> +#include <m_string.h> +#include "my_readline.h" + +static bool init_line_buffer(LINE_BUFFER *buffer,File file,ulong size, + ulong max_size); +static bool init_line_buffer_from_string(LINE_BUFFER *buffer,my_string str); +static uint fill_buffer(LINE_BUFFER *buffer); +static char *intern_read_line(LINE_BUFFER *buffer,uint *out_length); + + +LINE_BUFFER *batch_readline_init(ulong max_size,FILE *file) +{ + LINE_BUFFER *line_buff; + if (!(line_buff=(LINE_BUFFER*) my_malloc(sizeof(*line_buff),MYF(MY_WME)))) + return 0; + if (init_line_buffer(line_buff,fileno(file),IO_SIZE,max_size)) + { + my_free((char*) line_buff,MYF(0)); + return 0; + } + return line_buff; +} + + +char *batch_readline(LINE_BUFFER *line_buff) +{ + char *pos; + uint out_length; + + if (!(pos=intern_read_line(line_buff,&out_length))) + return 0; + if (out_length && pos[out_length-1] == '\n') + out_length--; /* Remove '\n' */ + pos[out_length]=0; + return pos; +} + + +void batch_readline_end(LINE_BUFFER *line_buff) +{ + if (line_buff) + { + my_free((gptr) line_buff->buffer,MYF(MY_ALLOW_ZERO_PTR)); + my_free((char*) line_buff,MYF(0)); + } +} + + +LINE_BUFFER *batch_readline_command(my_string str) +{ + LINE_BUFFER *line_buff; + if (!(line_buff=(LINE_BUFFER*) my_malloc(sizeof(*line_buff),MYF(MY_WME)))) + return 0; + if (init_line_buffer_from_string(line_buff,str)) + { + my_free((char*) line_buff,MYF(0)); + return 0; + } + return line_buff; +} + + +/***************************************************************************** + Functions to handle buffered readings of lines from a stream +******************************************************************************/ + +static bool +init_line_buffer(LINE_BUFFER *buffer,File file,ulong size,ulong max_buffer) +{ + bzero((char*) buffer,sizeof(buffer[0])); + buffer->file=file; + buffer->bufread=size; + buffer->max_size=max_buffer; + if (!(buffer->buffer = (char*) my_malloc(buffer->bufread+1, + MYF(MY_WME | MY_FAE)))) + return 1; + buffer->end_of_line=buffer->end=buffer->buffer; + buffer->buffer[0]=0; /* For easy start test */ + return 0; +} + + +static bool init_line_buffer_from_string(LINE_BUFFER *buffer,my_string str) +{ + uint length; + bzero((char*) buffer,sizeof(buffer[0])); + length=strlen(str); + if (!(buffer->buffer=buffer->start_of_line=buffer->end_of_line= + (char*)my_malloc(length+2,MYF(MY_FAE)))) + return 1; + memcpy(buffer->buffer,str,length); + buffer->buffer[length]='\n'; + buffer->buffer[length+1]=0; + buffer->end=buffer->buffer+length+1; + buffer->eof=1; + buffer->max_size=1; + return 0; +} + + +static void free_line_buffer(LINE_BUFFER *buffer) +{ + if (buffer->buffer) + { + my_free((gptr) buffer->buffer,MYF(0)); + buffer->buffer=0; + } +} + + +/* Fill the buffer retaining the last n bytes at the beginning of the + newly filled buffer (for backward context). Returns the number of new + bytes read from disk. */ + + +static uint fill_buffer(LINE_BUFFER *buffer) +{ + uint read_count; + uint bufbytes= (uint) (buffer->end - buffer->start_of_line); + + if (buffer->eof) + return 0; /* Everything read */ + + /* See if we need to grow the buffer. */ + + for (;;) + { + uint start_offset=(uint) (buffer->start_of_line - buffer->buffer); + read_count=(buffer->bufread - bufbytes)/IO_SIZE; + if ((read_count*=IO_SIZE)) + break; + buffer->bufread *= 2; + if (!(buffer->buffer = (char*) my_realloc(buffer->buffer, + buffer->bufread+1, + MYF(MY_WME | MY_FAE)))) + return (uint) -1; + buffer->start_of_line=buffer->buffer+start_offset; + buffer->end=buffer->buffer+bufbytes; + } + + /* Shift stuff down. */ + if (buffer->start_of_line != buffer->buffer) + { + bmove(buffer->buffer,buffer->start_of_line,(uint) bufbytes); + buffer->end=buffer->buffer+bufbytes; + } + + /* Read in new stuff. */ + if ((read_count= my_read(buffer->file, (byte*) buffer->end, read_count, + MYF(MY_WME))) == MY_FILE_ERROR) + return read_count; + + DBUG_PRINT("fill_buff", ("Got %d bytes", read_count)); + + /* Kludge to pretend every nonempty file ends with a newline. */ + if (!read_count && bufbytes && buffer->end[-1] != '\n') + { + buffer->eof = read_count = 1; + *buffer->end = '\n'; + } + buffer->end_of_line=(buffer->start_of_line=buffer->buffer)+bufbytes; + buffer->end+=read_count; + *buffer->end=0; /* Sentinel */ + return read_count; +} + + + +char *intern_read_line(LINE_BUFFER *buffer,uint *out_length) +{ + char *pos; + uint length; + DBUG_ENTER("intern_read_line"); + + buffer->start_of_line=buffer->end_of_line; + for (;;) + { + pos=buffer->end_of_line; + while (*pos != '\n' && *pos) + pos++; + if (pos == buffer->end) + { + if ((uint) (pos - buffer->start_of_line) < buffer->max_size) + { + if (!(length=fill_buffer(buffer)) || length == (uint) -1) + DBUG_RETURN(0); + continue; + } + pos--; /* break line here */ + } + buffer->end_of_line=pos+1; + *out_length=(uint) (pos + 1 - buffer->eof - buffer->start_of_line); + DBUG_RETURN(buffer->start_of_line); + } +} |