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Diffstat (limited to '')
-rw-r--r-- | client/readline.cc | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/client/readline.cc b/client/readline.cc new file mode 100644 index 00000000..e4014658 --- /dev/null +++ b/client/readline.cc @@ -0,0 +1,262 @@ +/* + Copyright (c) 2000, 2011, Oracle and/or its affiliates. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA +*/ + +/* readline for batch mode */ + +#include <my_global.h> +#include <my_sys.h> +#include <m_string.h> +#include <my_dir.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,char * str); +static size_t fill_buffer(LINE_BUFFER *buffer); +static char *intern_read_line(LINE_BUFFER *buffer, ulong *out_length); + + +LINE_BUFFER *batch_readline_init(ulong max_size,FILE *file) +{ + LINE_BUFFER *line_buff; + +#ifndef _WIN32 + MY_STAT input_file_stat; + if (my_fstat(fileno(file), &input_file_stat, MYF(MY_WME)) || + MY_S_ISDIR(input_file_stat.st_mode) || + MY_S_ISBLK(input_file_stat.st_mode)) + return 0; +#endif + + if (!(line_buff=(LINE_BUFFER*) + my_malloc(PSI_NOT_INSTRUMENTED, sizeof(*line_buff), + MYF(MY_WME | MY_ZEROFILL)))) + return 0; + if (init_line_buffer(line_buff,my_fileno(file),IO_SIZE,max_size)) + { + my_free(line_buff); + return 0; + } + return line_buff; +} + + +char *batch_readline(LINE_BUFFER *line_buff, bool binary_mode) +{ + char *pos; + ulong UNINIT_VAR(out_length); + + if (!(pos=intern_read_line(line_buff, &out_length))) + return 0; + if (out_length && pos[out_length-1] == '\n') + { + /* Remove '\n' */ + if (--out_length && !binary_mode && pos[out_length-1] == '\r') + /* Remove '\r' */ + out_length--; + } + line_buff->read_length=out_length; + pos[out_length]=0; + return pos; +} + + +void batch_readline_end(LINE_BUFFER *line_buff) +{ + if (line_buff) + { + my_free(line_buff->buffer); + my_free(line_buff); + } +} + + +LINE_BUFFER *batch_readline_command(LINE_BUFFER *line_buff, char * str) +{ + if (!line_buff) + if (!(line_buff=(LINE_BUFFER*) + my_malloc(PSI_NOT_INSTRUMENTED, sizeof(*line_buff), + MYF(MY_WME | MY_ZEROFILL)))) + return 0; + if (init_line_buffer_from_string(line_buff,str)) + { + my_free(line_buff); + 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) +{ + buffer->file=file; + buffer->bufread=size; + buffer->max_size=max_buffer; + if (!(buffer->buffer = (char*) my_malloc(PSI_NOT_INSTRUMENTED, + 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; +} + +/* + init_line_buffer_from_string can be called on the same buffer + several times. the resulting buffer will contain a + concatenation of all strings separated by spaces +*/ +static bool init_line_buffer_from_string(LINE_BUFFER *buffer,char * str) +{ + uint old_length=(uint)(buffer->end - buffer->buffer); + uint length= (uint) strlen(str); + if (!(buffer->buffer= buffer->start_of_line= buffer->end_of_line= + (char*) my_realloc(PSI_NOT_INSTRUMENTED, buffer->buffer, + old_length+length+2, MYF(MY_FAE|MY_ALLOW_ZERO_PTR)))) + return 1; + buffer->end= buffer->buffer + old_length; + if (old_length) + buffer->end[-1]=' '; + memcpy(buffer->end, str, length); + buffer->end[length]= '\n'; + buffer->end[length+1]= 0; + buffer->end+= length+1; + buffer->eof=1; + buffer->max_size=1; + return 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 size_t fill_buffer(LINE_BUFFER *buffer) +{ + size_t 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; + if (buffer->bufread * 2 > buffer->max_size) + { + /* + So we must grow the buffer but we cannot due to the max_size limit. + Return 0 w/o setting buffer->eof to signal this condition. + */ + return 0; + } + buffer->bufread *= 2; + if (!(buffer->buffer = (char*) my_realloc(PSI_NOT_INSTRUMENTED, + buffer->buffer, buffer->bufread+1, + MYF(MY_WME | MY_FAE)))) + { + buffer->error= my_errno; + return (size_t) -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, (uchar*) buffer->end, read_count, + MYF(MY_WME))) == MY_FILE_ERROR) + { + buffer->error= my_errno; + return (size_t) -1; + } + + DBUG_PRINT("fill_buff", ("Got %lu bytes", (ulong) read_count)); + + if (!read_count) + { + buffer->eof = 1; + /* Kludge to pretend every nonempty file ends with a newline. */ + if (bufbytes && buffer->end[-1] != '\n') + { + 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, ulong *out_length) +{ + char *pos; + size_t length; + DBUG_ENTER("intern_read_line"); + + buffer->start_of_line=buffer->end_of_line; + for (;;) + { + pos=buffer->end_of_line; + while (*pos != '\n' && pos != buffer->end) + pos++; + if (pos == buffer->end) + { + /* + fill_buffer() can return NULL on EOF (in which case we abort), + on error, or when the internal buffer has hit the size limit. + In the latter case return what we have read so far and signal + string truncation. + */ + if (!(length= fill_buffer(buffer))) + { + if (buffer->eof) + DBUG_RETURN(0); + } + else if (length == (size_t) -1) + DBUG_RETURN(NULL); + else + continue; + pos--; /* break line here */ + buffer->truncated= 1; + } + else + buffer->truncated= 0; + buffer->end_of_line=pos+1; + *out_length=(ulong) (pos + 1 - buffer->eof - buffer->start_of_line); + DBUG_RETURN(buffer->start_of_line); + } +} |