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Diffstat (limited to 'readline/histfile.c')
| -rw-r--r-- | readline/histfile.c | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/readline/histfile.c b/readline/histfile.c new file mode 100644 index 00000000000..3325b7fc1f7 --- /dev/null +++ b/readline/histfile.c @@ -0,0 +1,376 @@ +/* histfile.c - functions to manipulate the history file. */ + +/* Copyright (C) 1989, 1992 Free Software Foundation, Inc. + + This file contains the GNU History Library (the Library), a set of + routines for managing the text of previously typed lines. + + The Library 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; either version 1, or (at your option) + any later version. + + The 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 + General Public License for more details. + + The GNU General Public License is often shipped with GNU software, and + is generally kept in a file called COPYING or LICENSE. If you do not + have a copy of the license, write to the Free Software Foundation, + 675 Mass Ave, Cambridge, MA 02139, USA. */ + +/* The goal is to make the implementation transparent, so that you + don't have to know what data types are used, just what functions + you can call. I think I have done that. */ +#define READLINE_LIBRARY + +#if defined (HAVE_CONFIG_H) +# include <config.h> +#endif + +#include <stdio.h> + +#include <sys/types.h> +#ifndef _MINIX +# include <sys/file.h> +#endif +#include <sys/stat.h> +#include <fcntl.h> + +#if defined (HAVE_STDLIB_H) +# include <stdlib.h> +#else +# include "ansi_stdlib.h" +#endif /* HAVE_STDLIB_H */ + +#if defined (HAVE_UNISTD_H) +# include <unistd.h> +#endif + +#if defined (HAVE_STRING_H) +# include <string.h> +#else +# include <strings.h> +#endif /* !HAVE_STRING_H */ + +#if defined (__EMX__) +# ifndef O_BINARY +# define O_BINARY 0 +# endif +#else /* !__EMX__ */ + /* If we're not compiling for __EMX__, we don't want this at all. Ever. */ +# undef O_BINARY +# define O_BINARY 0 +#endif /* !__EMX__ */ + +#include <errno.h> +#if !defined (errno) +extern int errno; +#endif /* !errno */ + +#include "history.h" +#include "histlib.h" + +/* Functions imported from shell.c */ +extern char *get_env_value (); + +extern char *xmalloc (), *xrealloc (); + +/* Return the string that should be used in the place of this + filename. This only matters when you don't specify the + filename to read_history (), or write_history (). */ +static char * +history_filename (filename) + char *filename; +{ + char *return_val, *home; + int home_len; + + return_val = filename ? savestring (filename) : (char *)NULL; + + if (return_val) + return (return_val); + + home = get_env_value ("HOME"); + + if (home == 0) + { + home = "."; + home_len = 1; + } + else + home_len = strlen (home); + + return_val = xmalloc (2 + home_len + 8); /* strlen(".history") == 8 */ + strcpy (return_val, home); + return_val[home_len] = '/'; + strcpy (return_val + home_len + 1, ".history"); + + return (return_val); +} + +/* Add the contents of FILENAME to the history list, a line at a time. + If FILENAME is NULL, then read from ~/.history. Returns 0 if + successful, or errno if not. */ +int +read_history (filename) + char *filename; +{ + return (read_history_range (filename, 0, -1)); +} + +/* Read a range of lines from FILENAME, adding them to the history list. + Start reading at the FROM'th line and end at the TO'th. If FROM + is zero, start at the beginning. If TO is less than FROM, read + until the end of the file. If FILENAME is NULL, then read from + ~/.history. Returns 0 if successful, or errno if not. */ +int +read_history_range (filename, from, to) + char *filename; + int from, to; +{ + register int line_start, line_end; + char *input, *buffer; + int file, current_line; + struct stat finfo; + size_t file_size; + + buffer = (char *)NULL; + input = history_filename (filename); + file = open (input, O_RDONLY|O_BINARY, 0666); + + if ((file < 0) || (fstat (file, &finfo) == -1)) + goto error_and_exit; + + file_size = (size_t)finfo.st_size; + + /* check for overflow on very large files */ + if (file_size != finfo.st_size || file_size + 1 < file_size) + { +#if defined (EFBIG) + errno = EFBIG; +#endif + goto error_and_exit; + } + + buffer = xmalloc (file_size + 1); +#if 0 + if (read (file, buffer, file_size) != file_size) +#else + if (read (file, buffer, file_size) < 0) +#endif + { + error_and_exit: + if (file >= 0) + close (file); + + FREE (input); + FREE (buffer); + + return (errno); + } + + close (file); + + /* Set TO to larger than end of file if negative. */ + if (to < 0) + to = file_size; + + /* Start at beginning of file, work to end. */ + line_start = line_end = current_line = 0; + + /* Skip lines until we are at FROM. */ + while (line_start < file_size && current_line < from) + { + for (line_end = line_start; line_end < file_size; line_end++) + if (buffer[line_end] == '\n') + { + current_line++; + line_start = line_end + 1; + if (current_line == from) + break; + } + } + + /* If there are lines left to gobble, then gobble them now. */ + for (line_end = line_start; line_end < file_size; line_end++) + if (buffer[line_end] == '\n') + { + buffer[line_end] = '\0'; + + if (buffer[line_start]) + add_history (buffer + line_start); + + current_line++; + + if (current_line >= to) + break; + + line_start = line_end + 1; + } + + FREE (input); + FREE (buffer); + + return (0); +} + +/* Truncate the history file FNAME, leaving only LINES trailing lines. + If FNAME is NULL, then use ~/.history. */ +int +history_truncate_file (fname, lines) + char *fname; + int lines; +{ + register int i; + int file, chars_read; + char *buffer, *filename; + struct stat finfo; + size_t file_size; + + buffer = (char *)NULL; + filename = history_filename (fname); + file = open (filename, O_RDONLY|O_BINARY, 0666); + + if (file == -1 || fstat (file, &finfo) == -1) + goto truncate_exit; + + file_size = (size_t)finfo.st_size; + + /* check for overflow on very large files */ + if (file_size != finfo.st_size || file_size + 1 < file_size) + { + close (file); +#if defined (EFBIG) + errno = EFBIG; +#endif + goto truncate_exit; + } + + buffer = xmalloc (file_size + 1); + chars_read = read (file, buffer, file_size); + close (file); + + if (chars_read <= 0) + goto truncate_exit; + + /* Count backwards from the end of buffer until we have passed + LINES lines. */ + for (i = chars_read - 1; lines && i; i--) + { + if (buffer[i] == '\n') + lines--; + } + + /* If this is the first line, then the file contains exactly the + number of lines we want to truncate to, so we don't need to do + anything. It's the first line if we don't find a newline between + the current value of i and 0. Otherwise, write from the start of + this line until the end of the buffer. */ + for ( ; i; i--) + if (buffer[i] == '\n') + { + i++; + break; + } + + /* Write only if there are more lines in the file than we want to + truncate to. */ + if (i && ((file = open (filename, O_WRONLY|O_TRUNC|O_BINARY, 0600)) != -1)) + { + write (file, buffer + i, file_size - i); + +#if defined (__BEOS__) + /* BeOS ignores O_TRUNC. */ + ftruncate (file, file_size - i); +#endif + + close (file); + } + + truncate_exit: + + FREE (buffer); + + free (filename); + return 0; +} + +/* Workhorse function for writing history. Writes NELEMENT entries + from the history list to FILENAME. OVERWRITE is non-zero if you + wish to replace FILENAME with the entries. */ +static int +history_do_write (filename, nelements, overwrite) + char *filename; + int nelements, overwrite; +{ + register int i; + char *output; + int file, mode; + + mode = overwrite ? O_WRONLY|O_CREAT|O_TRUNC|O_BINARY : O_WRONLY|O_APPEND|O_BINARY; + output = history_filename (filename); + + if ((file = open (output, mode, 0600)) == -1) + { + FREE (output); + return (errno); + } + + if (nelements > history_length) + nelements = history_length; + + /* Build a buffer of all the lines to write, and write them in one syscall. + Suggested by Peter Ho (peter@robosts.oxford.ac.uk). */ + { + HIST_ENTRY **the_history; /* local */ + register int j; + int buffer_size; + char *buffer; + + the_history = history_list (); + /* Calculate the total number of bytes to write. */ + for (buffer_size = 0, i = history_length - nelements; i < history_length; i++) + buffer_size += 1 + strlen (the_history[i]->line); + + /* Allocate the buffer, and fill it. */ + buffer = xmalloc (buffer_size); + + for (j = 0, i = history_length - nelements; i < history_length; i++) + { + strcpy (buffer + j, the_history[i]->line); + j += strlen (the_history[i]->line); + buffer[j++] = '\n'; + } + + write (file, buffer, buffer_size); + free (buffer); + } + + close (file); + + FREE (output); + + return (0); +} + +/* Append NELEMENT entries to FILENAME. The entries appended are from + the end of the list minus NELEMENTs up to the end of the list. */ +int +append_history (nelements, filename) + int nelements; + char *filename; +{ + return (history_do_write (filename, nelements, HISTORY_APPEND)); +} + +/* Overwrite FILENAME with the current history. If FILENAME is NULL, + then write the history list to ~/.history. Values returned + are as in read_history ().*/ +int +write_history (filename) + char *filename; +{ + return (history_do_write (filename, history_length, HISTORY_OVERWRITE)); +} |