Minix1.1/user/commands/mined1.c
/*
* Part one of the mined editor.
*/
/*
* Author: Michiel Huisjes.
*
* 1. General remarks.
*
* Mined is a screen editor designed for the minix operating system.
* It is meant to be used on files not larger than 50K and to be fast.
* When mined starts up, it reads the file into its memory to minimize
* disk access. The only time that disk access is needed is when certain
* save, write or copy commands are given.
*
* Mined has the style of Emacs or Jove, that means that there are no modes.
* Each character has its own entry in an 256 pointer to function array,
* which is called when that character is typed. Only ASCII characters are
* connected with a function that inserts that character at the current
* location in the file. Two execptions are <linefeed> and <tab> which are
* inserted as well. Note that the mapping between commands and functions
* called is implicit in the table. Changing the mapping just implies
* changing the pointers in this table.
*
* The display consists of SCREENMAX + 1 lines and XMAX + 1 characters. When
* a line is larger (or gets larger during editing) than XBREAK characters,
* the line is either shifted SHIFT_SIZE characters to the left (which means
* that the first SHIFT_SIZE characters are not printed) or the end of the
* line is marked with the SHIFT_MARK character and the rest of the line is
* not printed. A line can never exceed MAX_CHARS characters. Mined will
* always try to keep the cursor on the same line and same (relative)
* x-coordinate if nothing changed. So if you scroll one line up, the cursor
* stays on the same line, or when you move one line down, the cursor will
* move to the same place on the line as it was on the previous.
* Every character on the line is available for editing including the
* linefeed at the the of the line. When the linefeed is deleted, the current
* line and the next line are joined. The last character of the file (which
* is always a linefeed) can never be deleted.
* The bottomline (as indicated by YMAX + 1) is used as a status line during
* editing. This line is usually blank or contains information mined needs
* during editing. This information (or rather questions) is displayed in
* reverse video.
*
* The terminal modes are changed completely. All signals like start/stop,
* interrupt etc. are unset. The only signal that remains is the quit signal.
* The quit signal (^\) is the general abort signal for mined. Typing a ^\
* during searching or when mined is asking for filenames, etc. will abort
* the function and mined will return to the main loop. Sending a quit
* signal during the main loop will abort the session (after confirmation)
* and the file is not (!) saved.
* The session will also be aborted when an unrecoverable error occurs. E.g
* when there is no more memory available. If the file has been modified,
* mined will ask if the file has to be saved or not.
* If there is no more space left on the disk, mined will just give an error
* message and continue.
*
* The number of system calls are minized. This is done to keep the editor
* as fast as possible. I/O is done in SCREEN_SIZE reads/writes. Accumulated
* output is also flushed at the end of each character typed.
*
* 2. Regular expressions
*
* Mined has a build in regular expression matcher, which is used for
* searching and replace routines. A regular expression consists of a
* sequence of:
*
* 1. A normal character matching that character.
* 2. A . matching any character.
* 3. A ^ matching the begin of a line.
* 4. A $ (as last character of the pattern) mathing the end of a line.
* 5. A \<character> matching <character>.
* 6. A number of characters enclosed in [] pairs matching any of these
* characters. A list of characters can be indicated by a '-'. So
* [a-z] matches any letter of the alphabet. If the first character
* after the '[' is a '^' then the set is negated (matching none of
* the characters).
* A ']', '^' or '-' can be escaped by putting a '\' in front of it.
* Of course this means that a \ must be represented by \\.
* 7. If one of the expressions as described in 1-6 is followed by a
* '*' than that expressions matches a sequence of 0 or more of
* that expression.
*
* Parsing of regular expression is done in two phases. In the first phase
* the expression is compiled into a more comprehensible form. In the second
* phase the actual matching is done. For more details see 3.6.
*
*
* 3. Implementation of mined.
*
* 3.1 Data structures.
*
* The main data structures are as follows. The whole file is kept in a
* double linked list of lines. The LINE structure looks like this:
*
* typedef struct Line {
* struct Line *next;
* struct Line *prev;
* char *text;
* unsigned char shift_count;
* } LINE;
*
* Each line entry contains a pointer to the next line, a pointer to the
* previous line and a pointer to the text of that line. A special field
* shift_count contains the number of shifts (in units of SHIFT_SIZE)
* that is performed on that line. The total size of the structure is 7
* bytes so a file consisting of 1000 empty lines will waste a lot of
* memory. A LINE structure is allocated for each line in the file. After
* that the number of characters of the line is counted and sufficient
* space is allocated to store them (including a linefeed and a '\0').
* The resulting address is assigned to the text field in the structure.
*
* A special structure is allocated and its address is assigned to the
* variable header as well as the variable tail. The text field of this
* structure is set to NIL_PTR. The tail->prev of this structure points
* to the last LINE of the file and the header->next to the first LINE.
* Other LINE *variables are top_line and bot_line which point to the
* first line resp. the last line on the screen.
* Two other variables are important as well. First the LINE *cur_line,
* which points to the LINE currently in use and the char *cur_text,
* which points to the character at which the cursor stands.
* Whenever an ASCII character is typed, a new line is build with this
* character inserted. Then the old data space (pointed to by
* cur_line->text) is freed, data space for the new line is allocated and
* assigned to cur_line->text.
*
* Two global variables called x and y represent the x and y coordinates
* from the cursor. The global variable nlines contains the number of
* lines in the file. Last_y indicates the maximum y coordinate of the
* screen (which is usually SCREENMAX).
*
* A few strings must be initialized by hand before compiling mined.
* These string are enter_string, which is printed upon entering mined,
* rev_video (turn on reverse video), normal_video, rev_scroll (perform a
* reverse scroll) and pos_string. The last string should hold the
* absolute position string to be printed for cursor motion. The #define
* X_PLUS and Y_PLUS should contain the characters to be added to the
* coordinates x and y (both starting at 0) to finish cursor positioning.
*
* 3.2 Starting up.
*
* Mined can be called with or without argument and the function
* load_file () is called with these arguments. load_file () checks
* if the file exists if it can be read and if it is writable and
* sets the writable flag accordingly. If the file can be read,
* load_file () reads a line from the file and stores this line into
* a structure by calling install_line () and line_insert () which
* installs the line into the double linked list, until the end of the
* file is reached.
* Lines are read by the function get_line (), which buffers the
* reading in blocks of SCREEN_SIZE. Load_file () also initializes the
* LINE *variables described above.
*
* 3.3 Moving around.
*
* Several commands are implemented for moving through the file.
* Moving up (UP), down (DN) left (LF) and right (RT) are done by the
* arrow keys. Moving one line below the screen scrolls the screen one
* line up. Moving one line above the screen scrolls the screen one line
* down. The functions forward_scroll () and reverse_scroll () take care
* of that.
* Several other move functions exist: move to begin of line (BL), end of
* line (EL) top of screen (HIGH), bottom of screen (LOW), top of file
* (HO), end of file (EF), scroll one page down (PD), scroll one page up
* (PU), scroll one line down (SD), scroll one line up (SU) and move to a
* certain line number (GOTO).
* Two functions called MN () and MP () each move one word further or
* backwards. A word is a number of non-blanks seperated by a space, a
* tab or a linefeed.
*
* 3.4 Modifying text.
*
* The modifying commands can be separated into two modes. The first
* being inserting text, and the other deleting text. Two functions are
* created for these purposes: insert () and delete (). Both are capable
* of deleting or inserting large amounts of text as well as one
* character. Insert () must be given the line and location at which
* the text must be inserted. Is doesn't make any difference whether this
* text contains linefeeds or not. Delete () must be given a pointer to
* the start line, a pointer from where deleting should start on that
* line and the same information about the end position. The last
* character of the file will never be deleted. Delete () will make the
* necessary changes to the screen after deleting, but insert () won't.
* The functions for modifying text are: insert one char (S), insert a
* file (file_insert (fd)), insert a linefeed and put cursor back to
* end of line (LIB), delete character under the cursor (DCC), delete
* before cursor (even linefeed) (DPC), delete next word (DNW), delete
* previous word (DPC) and delete to end of line (if the cursor is at
* a linefeed delete line) (DLN).
*
* 3.5 Yanking.
*
* A few utilities are provided for yanking pieces of text. The function
* MA () marks the current position in the file. This is done by setting
* LINE *mark_line and char *mark_text to the current position. Yanking
* of text can be done in two modes. The first mode just copies the text
* from the mark to the current position (or visa versa) into a buffer
* (YA) and the second also deletes the text (DT). Both functions call
* the function set_up () with the delete flag on or off. Set_up ()
* checks if the marked position is still a valid one (by using
* check_mark () and legal ()), and then calls the function yank () with
* a start and end position in the file. This function copies the text
* into a scratch_file as indicated by the variable yank_file. This
* scratch_file is made uniq by the function scratch_file (). At the end
* of copying yank will (if necessary) delete the text. A global flag
* called yank_status keeps track of the buffer (or file) status. It is
* initialized on NOT_VALID and set to EMPTY (by set_up ()) or VALID (by
* yank ()). Several things can be done with the buffer. It can be
* inserted somewhere else in the file (PT) or it can be copied into
* another file (WB), which will be prompted for.
*
* 3.6 Search and replace routines.
*
* Searching for strings and replacing strings are done by regular
* expressions. For any expression the function compile () is called
* with as argument the expression to compile. Compile () returns a
* pointer to a structure which looks like this:
*
* typedef struct regex {
* union {
* char *err_mess;
* int *expression;
* } result;
* char status;
* char *start_ptr;
* char *end_ptr;
* } REGEX;
*
* If something went wrong during compiling (e.g. an illegal expression
* was given), the function reg_error () is called, which sets the status
* field to REG_ERROR and the err_mess field to the error message. If the
* match must be anchored at the beginning of the line (end of line), the
* status field is set to BEGIN_LINE (END_LINE). If none of these special
* cases are true, the field is set to 0 and the function finished () is
* called. Finished () allocates space to hold the compiled expression
* and copies this expression into the expression field of the union
* (bcopy ()). Matching is done by the routines match() and line_check().
* Match () takes as argument the REGEX *program, a pointer to the
* startposition on the current line, and a flag indicating FORWARD or
* REVERSE search. Match () checks out the whole file until a match is
* found. If match is found it returns a pointer to the line in which the
* match was found else it returns a NIL_LINE. Line_check () takes the
* same arguments, but return either MATCH or NO_MATCH.
* During checking, the start_ptr and end_ptr fields of the REGEX
* structure are assigned to the start and end of the match.
* Both functions try to find a match by walking through the line
* character by character. For each possibility, the function
* check_string () is called with as arguments the REGEX *program and the
* string to search in. It starts walking through the expression until
* the end of the expression or the end of the string is reached.
* Whenever a * is encountered, this position of the string is marked,
* the maximum number of matches are performed and the function star ()
* is called in order to try to find the longest match possible. Star ()
* takes as arguments the REGEX program, the current position of the
* string, the marked position and the current position of the expression
* Star () walks from the current position of the string back to the
* marked position, and calls string_check () in order to find a match.
* It returns MATCH or NO_MATCH, just as string_check () does.
* Searching is now easy. Both search routines (forward (SF) and
* backwards search (SR)) call search () with an apropiate message and a
* flag indicating FORWARD or REVERSE search. Search () will get an
* expression from the user by calling get_expression(). Get_expression()
* returns a pointer to a REGEX structure or NIL_REG upon errors and
* prompts for the expression. If no expression if given, the previous is
* used instead. After that search will call match (), and if a match is
* found, we can move to that place in the file by the functions find_x()
* and find_y () which will find display the match on the screen.
* Replacing can be done in two ways. A global replace (GR) or a line
* replace (LR). Both functions call change () with a message an a flag
* indicating global or line replacement. Change () will prompt for the
* expression and for the replacement. Every & in the replacement pattern
* means substitute the match instead. An & can be escaped by a \. When
* a match is found, the function substitute () will perform the
* substitution.
*
* 3.6 Miscellaneous commands.
*
* A few commands haven't be discussed yet. These are redraw the screen
* (RD) fork a shell (SH), print file status (FS), write file to disc
* (WT), insert a file at current position (IF), leave editor (XT) and
* visit another file (VI). The last two functions will check if the file
* has been modified. If it has, they will ask if you want to save the
* file by calling ask_save ().
* The function ESC () will repeat a command n times. It will prompt for
* the number. Aborting the loop can be done by sending the ^\ signal.
*
* 3.7 Utility functions.
*
* Several functions exists for internal use. First allocation routines:
* alloc (bytes) and newline () will return a pointer to free data space
* if the given size. If there is no more memory available, the function
* panic () is called.
* Signal handling: The only signal that can be send to mined is the
* SIGQUIT signal. This signal, functions as a general abort command.
* Mined will abort if the signal is given during the main loop. The
* function abort_mined () takes care of that.
* Panic () is a function with as argument a error message. It will print
* the message and the error number set by the kernel (errno) and will
* ask if the file must be saved or not. It resets the terminal
* (raw_mode ()) and exits.
* String handling routines like copy_string(to, from), length_of(string)
* and build_string (buffer, format, arg1, arg2, ...). The latter takes
* a description of the string out out the format field and puts the
* result in the buffer. (It works like printf (3), but then into a
* string). The functions status_line (string1, string2), error (string1,
* string2), clear_status () and bottom_line () all print information on
* the status line.
* Get_string (message, buffer) reads a string and getchar () reads one
* character from the terminal.
* Num_out ((long) number) prints the number into a 11 digit field
* without leading zero's. It returns a pointer to the resulting string.
* File_status () prints all file information on the status line.
* Set_cursor (x, y) prints the string to put the cursor at coordinates
* x and y.
* Output is done by four functions: writeline(fd,string), clear_buffer()
* write_char (fd, c) and flush_buffer (fd). Three defines are provided
* to write on filedescriptor STD_OUT (terminal) which is used normally:
* string_print (string), putchar (c) and flush (). All these functions
* use the global I/O buffer screen and the global index for this array
* called out_count. In this way I/O can be buffered, so that reads or
* writes can be done in blocks of SCREEN_SIZE size.
* The following functions all handle internal line maintenance. The
* function proceed (start_line, count) returns the count'th line after
* start_line. If count is negative, the count'th line before the
* start_line is returned. If header or tail is encountered then that
* will be returned. Display (x, y, start_line, count) displays count
* lines starting at coordinates [x, y] and beginning at start_line. If
* the header or tail is encountered, empty lines are displayed instead.
* The function reset (head_line, ny) reset top_line, last_y, bot_line,
* cur_line and y-coordinate. This is not a neat way to do the
* maintenance, but it sure saves a lot of code. It is usually used in
* combination with display ().
* Put_line(line, offset, clear_line), prints a line (skipping characters
* according to the line->shift_size field) until XBREAK - offset
* characters are printed or a '\n' is encountered. If clear_line is
* TRUE, spaces are printed until XBREAK - offset characters.
* Line_print (line) is a #define from put_line (line, 0, TRUE).
* Moving is done by the functions move_to (x, y), move_addres (address)
* and move (x, adress, y). This function is the most important one in
* mined. New_y must be between 0 and last_y, new_x can be about
* anything, address must be a pointer to an character on the current
* line (or y). Move_to () first adjust the y coordinate together with
* cur_line. If an address is given, it finds the corresponding
* x-coordinate. If an new x-coordinate was given, it will try to locate
* the corresponding character. After that it sets the shift_count field
* of cur_line to an apropiate number according to new_x. The only thing
* left to do now is to assign the new values to cur_line, cur_text, x
* and y.
*
* 4. Summary of commands.
*
* CURSOR MOTION
* up-arrow Move cursor 1 line up. At top of screen, reverse scroll
* down-arrow Move cursor 1 line down. At bottom, scroll forward.
* left-arrow Move cursor 1 character left or to end of previous line
* right-arrow Move cursor 1 character right or to start of next line
* CTRL-A Move cursor to start of current line
* CTRL-Z Move cursor to end of current line
* CTRL-^ Move cursor to top of screen
* CTRL-_ Move cursor to bottom of screen
* CTRL-F Forward to start of next word (even to next line)
* CTRL-B Backward to first character of previous word
*
* SCREEN MOTION
* Home key Move cursor to first character of file
* End key Move cursor to last character of file
* PgUp Scroll backward 1 page. Bottom line becomes top line
* PgD Scroll backward 1 page. Top line becomes bottom line
* CTRL-D Scroll screen down one line (reverse scroll)
* CTRL-U Scroll screen up one line (forward scroll)
*
* MODIFYING TEXT
* ASCII char Self insert character at cursor
* tab Insert tab at cursor
* backspace Delete the previous char (left of cursor), even line feed
* Del Delete the character under the cursor
* CTRL-N Delete next word
* CTRL-P Delete previous word
* CTRL-O Insert line feed at cursor and back up 1 character
* CTRL-T Delete tail of line (cursor to end); if empty, delete line
* CTRL-@ Set the mark (remember the current location)
* CTRL-K Delete text from the mark to current position save on file
* CTRL-C Save the text from the mark to the current position
* CTRL-Y Insert the contents of the save file at current position
* CTRL-Q Insert the contents of the save file into a new file
* CTRL-G Insert a file at the current position
*
* MISCELLANEOUS
* CTRL-E Erase and redraw the screen
* CTRL-V Visit file (read a new file); complain if old one changed
* CTRL-W Write the current file back to the disk
* numeric + Search forward (prompt for regular expression)
* numeric - Search backward (prompt for regular expression)
* numeric 5 Print the current status of the file
* CTRL-R (Global) Replace str1 by str2 (prompts for each string)
* CTRL-L (Line) Replace string1 by string2
* CTRL-S Fork off a shell and wait for it to finish
* CTRL-X EXIT (prompt if file modified)
* CTRL-] Go to a line. Prompts for linenumber
* CTRL-\ Abort whatever editor was doing and start again
* escape key Repeat a command count times; (prompts for count)
*/
/* ======================================================================== *
* Utilities *
* ======================================================================== */
#include "mined.h"
#include "signal.h"
#include "sgtty.h"
#ifdef UNIX
#include <errno.h>
#else
#include "errno.h"
#endif UNIX
extern int errno;
/*
* Print file status.
*/
FS()
{
fstatus(file_name[0] ? "" : "[buffer]", -1L);
}
/*
* Visit (edit) another file. If the file has been modified, ask the user if
* he wants to save it.
*/
VI()
{
char new_file[LINE_LEN]; /* Buffer to hold new file name */
if (modified == TRUE && ask_save() == ERRORS)
return;
/* Get new file name */
if (get_file("Visit file:", new_file) == ERRORS)
return;
/* Free old linked list, initialize global variables and load new file */
initialize();
#ifdef UNIX
tputs(CL, 0, _putchar);
#else
string_print (enter_string);
#endif UNIX
load_file(new_file[0] == '\0' ? NIL_PTR : new_file);
}
/*
* Write file in core to disc.
*/
WT()
{
register LINE *line;
register long count = 0L; /* Nr of chars written */
char file[LINE_LEN]; /* Buffer for new file name */
int fd; /* Filedescriptor of file */
if (modified == FALSE) {
error ("Write not necessary.", NIL_PTR);
return FINE;
}
/* Check if file_name is valid and if file can be written */
if (file_name[0] == '\0' || writable == FALSE) {
if (get_file("Enter file name:", file) != FINE)
return ERRORS;
copy_string(file_name, file); /* Save file name */
}
if ((fd = creat(file_name, 0644)) < 0) { /* Empty file */
error("Cannot create ", file_name);
writable = FALSE;
return ERRORS;
}
else
writable = TRUE;
clear_buffer();
status_line("Writing ", file_name);
for (line = header->next; line != tail; line = line->next) {
if (line->shift_count & DUMMY) {
if (line->next == tail && line->text[0] == '\n')
continue;
}
if (writeline(fd, line->text) == ERRORS) {
count = -1L;
break;
}
count += (long) length_of(line->text);
}
if (count > 0L && flush_buffer(fd) == ERRORS)
count = -1L;
(void) close(fd);
if (count == -1L)
return ERRORS;
modified = FALSE;
rpipe = FALSE; /* File name is now assigned */
/* Display how many chars (and lines) were written */
fstatus("Wrote", count);
return FINE;
}
/*
* Call an interactive shell.
*/
SH()
{
register int w;
int pid, status;
switch (pid = fork()) {
case -1: /* Error */
error("Cannot fork.", NIL_PTR);
return;
case 0: /* This is the child */
set_cursor(0, YMAX);
putchar('\n');
flush();
raw_mode(OFF);
if (rpipe) { /* Fix stdin */
close (0);
if (open("/dev/tty", 0) < 0)
exit (126);
}
execl("/bin/sh", "sh", "-i", 0);
exit(127); /* Exit with 127 */
default : /* This is the parent */
signal(SIGINT, SIG_IGN);
signal(SIGQUIT, SIG_IGN);
do {
w = wait(&status);
} while (w != -1 && w != pid);
}
raw_mode(ON);
RD();
if ((status >> 8) == 127) /* Child died with 127 */
error("Cannot exec /bin/sh (possibly not enough memory)", NIL_PTR);
else if ((status >> 8) == 126)
error("Cannot open /dev/tty as fd #0", NIL_PTR);
}
/*
* Proceed returns the count'th line after `line'. When count is negative
* it returns the count'th line before `line'. When the next (previous)
* line is the tail (header) indicating EOF (tof) it stops.
*/
LINE *proceed(line, count)
register LINE *line;
register int count;
{
if (count < 0)
while (count++ < 0 && line != header)
line = line->prev;
else
while (count-- > 0 && line != tail)
line = line->next;
return line;
}
/*
* Show concatenation of s1 and s2 on the status line (bottom of screen)
* If revfl is TRUE, turn on reverse video on both strings. Set stat_visible
* only if bottom_line is visible.
*/
bottom_line(revfl, s1, s2, inbuf, statfl)
FLAG revfl;
char *s1, *s2;
char *inbuf;
FLAG statfl;
{
int ret = FINE;
if (revfl == ON && stat_visible == TRUE)
clear_status ();
set_cursor(0, YMAX);
if (revfl == ON) { /* Print rev. start sequence */
#ifdef UNIX
tputs(SO, 0, _putchar);
#else
string_print(rev_video);
#endif UNIX
stat_visible = TRUE;
}
else /* Used as clear_status() */
stat_visible = FALSE;
putchar(' ');
if (s1 != NIL_PTR)
string_print(s1);
if (s2 != NIL_PTR)
string_print(s2);
putchar(' ');
if (inbuf != NIL_PTR)
ret = input(inbuf, statfl);
/* Print normal video */
#ifdef UNIX
tputs(SE, 0, _putchar);
tputs(CE, 0, _putchar);
#else
string_print(normal_video);
string_print(blank_line); /* Clear the rest of the line */
#endif UNIX
if (inbuf != NIL_PTR)
set_cursor(0, YMAX);
else
set_cursor(x, y); /* Set cursor back to old position */
flush(); /* Perform the actual write */
if (ret != FINE)
clear_status();
return ret;
}
/*
* Count_chars() count the number of chars that the line would occupy on the
* screen. Counting starts at the real x-coordinate of the line.
*/
count_chars(line)
LINE *line;
{
register int cnt = get_shift(line->shift_count) * -SHIFT_SIZE;
register char *textp = line->text;
/* Find begin of line on screen */
while (cnt < 0) {
if (is_tab(*textp++))
cnt = tab(cnt);
else
cnt++;
}
/* Count number of chars left */
cnt = 0;
while (*textp != '\n') {
if (is_tab(*textp++))
cnt = tab(cnt);
else
cnt++;
}
return cnt;
}
/*
* Move to coordinates nx, ny at screen. The caller must check that scrolling
* is not needed.
* If new_x is lower than 0 or higher than XBREAK, move_to() will check if
* the line can be shifted. If it can it sets(or resets) the shift_count field
* of the current line accordingly.
* Move also sets cur_text to the right char.
* If we're moving to the same x coordinate, try to move the the x-coordinate
* used on the other previous call.
*/
move(new_x, new_address, new_y)
register int new_x;
int new_y;
char *new_address;
{
register LINE *line = cur_line; /* For building new cur_line */
int shift = 0; /* How many shifts to make */
static int rel_x = 0; /* Remember relative x position */
int tx = x;
char *find_address();
/* Check for illegal values */
if (new_y < 0 || new_y > last_y)
return;
/* Adjust y-coordinate and cur_line */
if (new_y < y)
while (y != new_y) {
y--;
line = line->prev;
}
else
while (y != new_y) {
y++;
line = line->next;
}
/* Set or unset relative x-coordinate */
if (new_address == NIL_PTR) {
new_address = find_address(line, (new_x == x) ? rel_x : new_x , &tx);
if (new_x != x)
rel_x = tx;
new_x = tx;
}
else
rel_x = new_x = find_x(line, new_address);
/* Adjust shift_count if new_x lower than 0 or higher than XBREAK */
if (new_x < 0 || new_x >= XBREAK) {
if (new_x > XBREAK || (new_x == XBREAK && *new_address != '\n'))
shift = (new_x - XBREAK) / SHIFT_SIZE + 1;
else {
shift = new_x / SHIFT_SIZE;
if (new_x % SHIFT_SIZE)
shift--;
}
if (shift != 0) {
line->shift_count += shift;
new_x = find_x(line, new_address);
set_cursor(0, y);
line_print(line);
rel_x = new_x;
}
}
/* Assign and position cursor */
x = new_x;
cur_text = new_address;
cur_line = line;
set_cursor(x, y);
}
/*
* Find_x() returns the x coordinate belonging to address.
* (Tabs are expanded).
*/
find_x(line, address)
LINE *line;
char *address;
{
register char *textp = line->text;
register int nx = get_shift(line->shift_count) * -SHIFT_SIZE;
while (textp != address && *textp != '\0') {
if (is_tab(*textp++)) /* Expand tabs */
nx = tab(nx);
else
nx++;
}
return nx;
}
/*
* Find_address() returns the pointer in the line with offset x_coord.
* (Tabs are expanded).
*/
char *find_address(line, x_coord, old_x)
LINE *line;
int x_coord;
int *old_x;
{
register char *textp = line->text;
register int tx = get_shift(line->shift_count) * -SHIFT_SIZE;
while (tx < x_coord && *textp != '\n') {
if (is_tab(*textp)) {
if (*old_x - x_coord == 1 && tab(tx) > x_coord)
break; /* Moving left over tab */
else
tx = tab(tx);
}
else
tx++;
textp++;
}
*old_x = tx;
return textp;
}
/*
* Length_of() returns the number of characters int the string `string'
* excluding the '\0'.
*/
length_of(string)
register char *string;
{
register int count = 0;
if (string != NIL_PTR) {
while (*string++ != '\0')
count++;
}
return count;
}
/*
* Copy_string() copies the string `from' into the string `to'. `To' must be
* long enough to hold `from'.
*/
copy_string(to, from)
register char *to;
register char *from;
{
while (*to++ = *from++)
;
}
/*
* Reset assigns bot_line, top_line and cur_line according to `head_line'
* which must be the first line of the screen, and an y-coordinate,
* which will be the current y-coordinate (if it isn't larger than last_y)
*/
reset(head_line, screen_y)
LINE *head_line;
int screen_y;
{
register LINE *line;
top_line = line = head_line;
/* Search for bot_line (might be last line in file) */
for (last_y = 0; last_y < nlines - 1 && last_y < SCREENMAX
&& line->next != tail; last_y++)
line = line->next;
bot_line = line;
y = (screen_y > last_y) ? last_y : screen_y;
/* Set cur_line according to the new y value */
cur_line = proceed(top_line, y);
}
/*
* Set cursor at coordinates x, y.
*/
set_cursor(nx, ny)
int nx, ny;
{
#ifdef UNIX
extern char *tgoto();
tputs(tgoto(CM, nx, ny), 0, _putchar);
#else
string_print(pos_string);
putchar(X_PLUS + nx);
putchar(Y_PLUS + YMAX - ny);/* Driver has (0,0) at lower left corner */
#endif UNIX
}
/*
* Routine to open terminal when mined is used in a pipeline.
*/
open_device()
{
if ((input_fd = open("/dev/tty", 0)) < 0)
panic("Cannot open /dev/tty for read");
}
/*
* Getchar() reads one character from the terminal. The character must be
* masked with 0377 to avoid sign extension.
*/
getchar()
{
#ifdef UNIX
return (_getchar() & 0177);
#else
char c;
if (read(input_fd, &c, 1) != 1 && quit == FALSE)
panic("Can't read one char from fd #0");
return c & 0377;
#endif UNIX
}
/*
* Display() shows count lines on the terminal starting at the given
* coordinates. When the tail of the list is encountered it will fill the
* rest of the screen with blank_line's.
* When count is negative, a backwards print from `line' will be done.
*/
display(x_coord, y_coord, line, count)
int x_coord, y_coord;
register LINE *line;
register int count;
{
set_cursor(x_coord, y_coord);
/* Find new startline if count is negative */
if (count < 0) {
line = proceed(line, count);
count = -count;
}
/* Print the lines */
while (line != tail && count-- >= 0) {
line_print(line);
line = line->next;
}
/* Print the blank lines (if any) */
if (loading == FALSE) {
while (count-- >= 0) {
#ifdef UNIX
tputs(CE, 0, _putchar);
#else
string_print(blank_line);
#endif UNIX
putchar('\n');
}
}
}
/*
* Write_char does a buffered output.
*/
write_char(fd, c)
int fd;
char c;
{
screen [out_count++] = c;
if (out_count == SCREEN_SIZE) /* Flush on SCREEN_SIZE chars */
return flush_buffer(fd);
return FINE;
}
/*
* Writeline writes the given string on the given filedescriptor.
*/
writeline(fd, text)
register int fd;
register char *text;
{
while(*text)
if (write_char(fd, *text++) == ERRORS)
return ERRORS;
return FINE;
}
/*
* Put_line print the given line on the standard output. If offset is not zero
* printing will start at that x-coordinate. If the FLAG clear_line is TRUE,
* then (screen) line will be cleared when the end of the line has been
* reached.
*/
put_line(line, offset, clear_line)
LINE *line; /* Line to print */
int offset; /* Offset to start */
FLAG clear_line; /* Clear to eoln if TRUE */
{
register char *textp = line->text;
register int count = get_shift(line->shift_count) * -SHIFT_SIZE;
int tab_count; /* Used in tab expansion */
/* Skip all chars as indicated by the offset and the shift_count field */
while (count < offset) {
if (is_tab(*textp++))
count = tab(count);
else
count++;
}
while (*textp != '\n' && count < XBREAK) {
if (is_tab(*textp)) { /* Expand tabs to spaces */
tab_count = tab(count);
while (count < XBREAK && count < tab_count) {
count++;
putchar(' ');
}
textp++;
}
else {
if (*textp >= '\01' && *textp <= '\037') {
#ifdef UNIX
tputs(SO, 0, _putchar);
#else
string_print (rev_video);
#endif UNIX
putchar(*textp++ + '\100');
#ifdef UNIX
tputs(SE, 0, _putchar);
#else
string_print (normal_video);
#endif UNIX
}
else
putchar(*textp++);
count++;
}
}
/* If line is longer than XBREAK chars, print the shift_mark */
if (count == XBREAK && *textp != '\n')
putchar(SHIFT_MARK);
/* Clear the rest of the line is clear_line is TRUE */
if (clear_line == TRUE) {
#ifdef UNIX
tputs(CE, 0, _putchar);
#else
while (count++ <= XBREAK)
putchar(' ');
#endif UNIX
putchar('\n');
}
}
/*
* Flush the I/O buffer on filedescriptor fd.
*/
flush_buffer(fd)
int fd;
{
if (out_count <= 0) /* There is nothing to flush */
return FINE;
#ifdef UNIX
if (fd == STD_OUT) {
printf("%.*s", out_count, screen);
_flush();
}
else
#endif UNIX
if (write(fd, screen, out_count) != out_count) {
bad_write(fd);
return ERRORS;
}
clear_buffer(); /* Empty buffer */
return FINE;
}
/*
* Bad_write() is called when a write failed. Notify the user.
*/
bad_write(fd)
int fd;
{
if (fd == STD_OUT) /* Cannot write to terminal? */
exit(1);
clear_buffer();
build_string(text_buffer, "Command aborted: %s (File incomplete)",
(errno == ENOSPC || errno == -ENOSPC) ?
"No space on device" : "Write error");
error(text_buffer, NIL_PTR);
}
/*
* Catch the SIGQUIT signal (^\) send to mined. It turns on the quitflag.
*/
catch()
{
/* Reset the signal */
signal(SIGQUIT, catch);
quit = TRUE;
}
/*
* Abort_mined() will leave mined. Confirmation is asked first.
*/
abort_mined()
{
quit = FALSE;
/* Ask for confirmation */
status_line("Really abort? ", NIL_PTR);
if (getchar() != 'y') {
clear_status();
return;
}
/* Reset terminal */
raw_mode(OFF);
set_cursor(0, YMAX);
putchar('\n');
flush();
#ifdef UNIX
abort();
#else
exit(1);
#endif UNIX
}
#define UNDEF -1
/*
* Set and reset tty into CBREAK or old mode according to argument `state'. It
* also sets all signal characters (except for ^\) to UNDEF. ^\ is caught.
*/
raw_mode(state)
FLAG state;
{
static struct sgttyb old_tty;
static struct sgttyb new_tty;
static struct tchars old_tchars;
static struct tchars new_tchars = {UNDEF, '\034', UNDEF, UNDEF, UNDEF, UNDEF};
#ifdef UNIX
int ldisc;
#endif UNIX
if (state == OFF) {
ioctl(input_fd, TIOCSETP, &old_tty);
ioctl(input_fd, TIOCSETC, &old_tchars);
#ifdef UNIX
ldisc = NTTYDISC;
ioctl(input_fd, TIOCSETD, &ldisc);
#endif UNIX
return;
}
/* Save old tty settings */
ioctl(input_fd, TIOCGETC, &old_tchars);
ioctl(input_fd, TIOCGETP, &old_tty);
#ifdef UNIX
ldisc = OTTYDISC;
ioctl(input_fd, TIOCSETD, &ldisc);
#endif UNIX
/* Set tty to CBREAK mode */
ioctl(input_fd, TIOCGETP, &new_tty);
new_tty.sg_flags |= CBREAK;
new_tty.sg_flags &= ~ECHO;
ioctl(input_fd, TIOCSETP, &new_tty);
/* Unset signal chars */
ioctl(input_fd, TIOCSETC, &new_tchars); /* Only leaves you ^\ */
signal(SIGQUIT, catch); /* Which is caught */
}
/*
* Panic() is called with an error number and a message. It is called when
* something unrecoverable has happened.
* It writes the message to the terminal, resets the tty and exits.
* Ask the user if he wants to save his file.
*/
panic(message)
register char *message;
{
extern char yank_file[];
#ifdef UNIX
tputs(CL, 0, _putchar);
build_string(text_buffer, "%s\nError code %d\n", message, errno);
#else
build_string(text_buffer, "%s%s\nError code %d\n", enter_string, message, errno);
#endif UNIX
(void) write(STD_OUT, text_buffer, length_of(text_buffer));
if (loading == FALSE)
XT(); /* Check if file can be saved */
else
(void) unlink(yank_file);
raw_mode(OFF);
#ifdef UNIX
abort();
#else
exit(1);
#endif UNIX
}
#ifndef lint
typedef unsigned vir_bytes;
#define POINTER_SIZE (sizeof(char *))
#define cast(x) ((vir_bytes) (x))
#define align(x, a) (((x) + (a - 1)) & ~(a - 1))
#define BUSY 1
#define succ(p) (* (char **) (p))
#define is_busy(p) (cast(p) & BUSY)
#define set_busy(p) ((char *) (cast(p) | BUSY))
char *free_list;
/*
* Init_alloc() sets up the free list. The free list initially consists of
* MEMORY_SIZE bytes.
*/
init_alloc()
{
register char *ptr, *top;
extern char *sbrk();
/* Get data space for free list */
free_list = sbrk(POINTER_SIZE);
if ((ptr = sbrk(MEMORY_SIZE)) < 0)
panic("Bad memory allocation in startup");
top = sbrk(POINTER_SIZE);
/* Set up list */
succ(free_list) = ptr;
succ(ptr) = top;
succ(top) = NIL_PTR;
}
/*
* Allocate size bytes of memory.
*/
char *alloc(size)
unsigned size;
{
register char *p = free_list;
register char *next;
char *new;
unsigned len = align(size, POINTER_SIZE) + POINTER_SIZE;
p = free_list;
while ((next = succ(p)) != NIL_PTR) {
if (is_busy(next)) /* Already in use */
p = (char *) (cast(next) & ~BUSY);
else {
while ((new = succ(next)) != NIL_PTR && !is_busy(new))
next = new;
if (next - p >= len) { /* fits */
if ((new = p + len) < next) { /* too big */
succ(new) = next;
succ(p) = set_busy(new);
}
else
succ(p) = set_busy(next);
free_list = p;
return (p + POINTER_SIZE);
}
p = next;
}
}
if (loading == TRUE)
panic("File too big.");
panic("Out of memory.");
}
free_space(p)
register char *p;
{
p = (char *) (cast(p) - POINTER_SIZE);
*(vir_bytes *) (p) &= ~BUSY;
/* Pointer to free list should point to lowest address freed. */
if (free_list > p)
free_list = p;
}
#else
char *alloc(bytes)
int bytes;
{
extern char *malloc();
return malloc((unsigned) bytes);
}
free_space(p)
char *p;
{
free(p);
}
#endif lint
/* ======================================================================== *
* Main loops *
* ======================================================================== */
/* The mapping between input codes and functions. */
extern UP(), DN(), LF(), RT(), MN(), MP(), GOTO();
extern SD(), SU(), PD(), PU(), HO(), EF(), BL(), EL(), HIGH(), LOW();
extern S(), LIB(), DPC(), DCC(), DLN(), DNW(), DPW(), CTRL();
extern XT(), WT(), VI(), RD(), SH(), I(), FS(), ESC();
extern SF(), SR(), LR(), GR();
extern MA(), YA(), DT(), PT(), WB(), IF();
#ifdef UNIX
int (*key_map[128])() = { /* map ASCII characters to functions */
/* 000-017 */ MA, BL, MP, YA, SD, RD, MN, IF, DPC, S, S, DT, LR, S, DNW, LIB,
/* 020-037 */ DPW, WB, GR, SH, DLN, SU, VI, WT, XT, PT, EL, ESC, I, GOTO,
HIGH, LOW,
/* 040-057 */ S, S, S, S, S, S, S, S, S, S, S, PD, S, PU, S, S,
/* 060-077 */ S, S, DN, S, LF, FS, RT, S, UP, S, S, S, S, S, S, S,
/* 100-117 */ S, S, S, CTRL, S, EF, SF, S, HO, S, S, S, S, S, S, S,
/* 120-137 */ S, S, SR, S, S, S, S, S, S, S, S, S, S, S, S, S,
/* 140-157 */ S, S, S, S, S, S, S, S, S, S, S, S, S, S, S, S,
/* 160-177 */ S, S, S, S, S, S, S, S, S, S, S, S, S, S, S, DCC
};
#else
int (*key_map[256])() = { /* map ASCII characters to functions */
/* 000-017 */ I, BL, MP, YA, SD, RD, MN, IF, DPC, S, S, DT, LR, S, DNW, LIB,
/* 020-037 */ DPW, WB, GR, SH, DLN, SU, VI, WT, XT, PT, EL, ESC, I, GOTO,
HIGH, LOW,
/* 040-057 */ S, S, S, S, S, S, S, S, S, S, S, S, S, S, S, S,
/* 060-077 */ S, S, S, S, S, S, S, S, S, S, S, S, S, S, S, S,
/* 100-117 */ S, S, S, S, S, S, S, S, S, S, S, S, S, S, S, S,
/* 120-137 */ S, S, S, S, S, S, S, S, S, S, S, S, S, S, S, S,
/* 140-157 */ S, S, S, S, S, S, S, S, S, S, S, S, S, S, S, S,
/* 160-177 */ S, S, S, S, S, S, S, S, S, S, S, S, S, S, S, DCC,
/* 200-217 */ I, I, I, I, I, I, I, I, I, SR, I, I, SF, I, I, I,
/* 220-237 */ MA, I, I, I, I, I, I, I, I, I, I, CTRL, I, I, I, I,
/* 240-257 */ I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I,
/* 260-277 */ I, EF, DN, PD, LF, FS, RT, HO, UP, PU, I, I, I, I, I, I,
/* 300-317 */ I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I,
/* 320-337 */ I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I,
/* 340-357 */ I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I,
/* 360-377 */ I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I
};
#endif UNIX
int nlines; /* Number of lines in file */
LINE *header; /* Head of line list */
LINE *tail; /* Last line in line list */
LINE *cur_line; /* Current line in use */
LINE *top_line; /* First line of screen */
LINE *bot_line; /* Last line of screen */
char *cur_text; /* Current char on current line in use */
int last_y; /* Last y of screen. Usually SCREENMAX */
char screen[SCREEN_SIZE]; /* Output buffer for "writes" and "reads" */
int x, y; /* x, y coordinates on screen */
FLAG modified = FALSE; /* Set when file is modified */
FLAG stat_visible; /* Set if status_line is visible */
FLAG writable; /* Set if file cannot be written */
FLAG loading; /* Set if we are loading a file. */
FLAG quit = FALSE; /* Set when quit character is typed */
FLAG rpipe = FALSE; /* Set if file should be read from stdin */
int input_fd = 0; /* Fd for command input */
int out_count; /* Index in output buffer */
char file_name[LINE_LEN]; /* Name of file in use */
char text_buffer[MAX_CHARS]; /* Buffer for modifying text */
char blank_line[LINE_LEN]; /* Line filled with spaces */
/* Escape sequences. */
#ifdef UNIX
char *CE, *VS, *SO, *SE, *CL, *AL, *CM;
#else
char *enter_string = "\033 8\033~0"; /* String printed on entering mined */
char *pos_string = "\033"; /* Absolute cursor position */
char *rev_scroll = "\033~1"; /* String for reverse scrolling */
char *rev_video = "\033z\160"; /* String for starting reverse video */
char *normal_video = "\033z\007"; /* String for leaving reverse video */
#endif UNIX
/*
* Yank variables.
*/
FLAG yank_status = NOT_VALID; /* Status of yank_file */
char yank_file[] = "/tmp/mined.XXXXXX";
long chars_saved; /* Nr of chars in buffer */
/*
* Initialize is called when a another file is edited. It free's the allocated
* space and sets modified back to FALSE and fixes the header/tail pointer.
*/
initialize()
{
register LINE *line, *next_line;
/* Delete the whole list */
for (line = header->next; line != tail; line = next_line) {
next_line = line->next;
free_space(line->text);
free_space(line);
}
/* header and tail should point to itself */
line->next = line->prev = line;
x = y = 0;
rpipe = modified = FALSE;
}
/*
* Basename() finds the absolute name of the file out of a given path_name.
*/
char *basename(path)
char *path;
{
register char *ptr = path;
register char *last = NIL_PTR;
while (*ptr != '\0') {
if (*ptr == '/')
last = ptr;
ptr++;
}
if (last == NIL_PTR)
return path;
if (*(last + 1) == '\0') { /* E.g. /usr/tmp/pipo/ */
*last = '\0';
return basename(path);/* Try again */
}
return last + 1;
}
/*
* Load_file loads the file `file' into core. If file is a NIL_PTR or the file
* couldn't be opened, just some initializations are done, and a line consisting
* of a `\n' is installed.
*/
load_file(file)
char *file;
{
register LINE *line = header;
register int len;
long nr_of_chars = 0L;
int fd = -1; /* Filedescriptor for file */
nlines = 0; /* Zero lines to start with */
/* Open file */
writable = TRUE; /* Benefit of the doubt */
if (file == NIL_PTR) {
if (rpipe == FALSE)
status_line("No file.", NIL_PTR);
else {
fd = 0;
file = "standard input";
}
file_name[0] = '\0';
}
else {
copy_string(file_name, file); /* Save file name */
if (access(file, 0) < 0) /* Cannot access file. */
status_line("New file ", file);
else if ((fd = open(file, 0)) < 0)
status_line("Cannot open ", file);
else if (access(file, 2) != 0) /* Set write flag */
writable = FALSE;
}
/* Read file */
loading = TRUE; /* Loading file, so set flag */
if (fd >= 0) {
status_line("Reading ", file);
while ((len = get_line(fd, text_buffer)) != ERRORS) {
line = line_insert(line, text_buffer, len);
nr_of_chars += (long) len;
}
if (nlines == 0) /* The file was empty! */
line = line_insert(line, "\n", 1);
clear_buffer(); /* Clear output buffer */
cur_line = header->next;
fstatus("Read", nr_of_chars);
(void) close(fd); /* Close file */
}
else /* Just install a "\n" */
(void) line_insert(line, "\n", 1);
reset(header->next, 0); /* Initialize pointers */
/* Print screen */
display (0, 0, header->next, last_y);
move_to (0, 0);
flush(); /* Flush buffer */
loading = FALSE; /* Stop loading, reset flag */
}
/*
* Get_line reads one line from filedescriptor fd. If EOF is reached on fd,
* get_line() returns ERRORS, else it returns the length of the string.
*/
get_line(fd, buffer)
int fd;
register char *buffer;
{
static char *last = NIL_PTR;
static char *current = NIL_PTR;
static int read_chars;
register char *cur_pos = current;
char *begin = buffer;
do {
if (cur_pos == last) {
if ((read_chars = read(fd, screen, SCREEN_SIZE)) <= 0)
break;
last = &screen[read_chars];
cur_pos = screen;
}
if ((unsigned char) *cur_pos >= 0177 || *cur_pos == '\0')
panic ("File contains non-ascii characters");
} while ((*buffer++ = *cur_pos++) != '\n');
current = cur_pos;
if (read_chars <= 0) {
if (buffer == begin)
return ERRORS;
if (*(buffer - 1) != '\n')
if (loading == TRUE) /* Add '\n' to last line of file */
*buffer++ = '\n';
else {
*buffer = '\0';
return NO_LINE;
}
}
*buffer = '\0';
return buffer - begin;
}
/*
* Install_line installs the buffer into a LINE structure It returns a pointer
* to the allocated structure.
*/
LINE *install_line(buffer, length)
char *buffer;
int length;
{
register LINE *new_line = (LINE *) alloc(sizeof(LINE));
new_line->text = alloc(length + 1);
new_line->shift_count = 0;
copy_string(new_line->text, buffer);
return new_line;
}
main(argc, argv)
int argc;
char *argv[];
{
/* mined is the Monix editor for the IBM PC. */
register int index; /* Index in key table */
#ifdef UNIX
get_term();
tputs(VS, 0, _putchar);
tputs(CL, 0, _putchar);
#else
string_print(enter_string); /* Hello world */
for (index = 0; index < XMAX; index++) /* Fill blank_line with spaces*/
blank_line[index] = ' ';
blank_line[XMAX] = '\0';
#endif UNIX
if (!isatty(0)) { /* Reading from pipe */
if (argc != 1) {
write(2, "Cannot find terminal.\n", 22);
exit (1);
}
rpipe = TRUE;
modified = TRUE; /* Set modified so he can write */
open_device();
}
raw_mode(ON); /* Set tty to appropriate mode */
init_alloc();
header = tail = (LINE *) alloc(sizeof(LINE)); /* Make header of list*/
header->text = NIL_PTR;
header->next = tail->prev = header;
/* Load the file (if any) */
if (argc < 2)
load_file(NIL_PTR);
else {
(void) get_file(NIL_PTR, argv[1]); /* Truncate filename */
load_file(argv[1]);
}
/* Main loop of the editor. */
for (;;) {
index = getchar();
if (stat_visible == TRUE)
clear_status();
if (quit == TRUE)
abort_mined();
else { /* Call the function for this key */
(*key_map[index])(index);
flush(); /* Flush output (if any) */
if (quit == TRUE)
quit = FALSE;
}
}
/* NOTREACHED */
}
/* ======================================================================== *
* Miscellaneous *
* ======================================================================== */
/*
* Redraw the screen
*/
RD()
{
/* Clear screen */
#ifdef UNIX
tputs(VS, 0, _putchar);
tputs(CL, 0, _putchar);
#else
string_print(enter_string);
#endif UNIX
/* Print first page */
display(0, 0, top_line, last_y);
/* Clear last line */
set_cursor(0, YMAX);
#ifdef UNIX
tputs(CE, 0, _putchar);
#else
string_print(blank_line);
#endif UNIX
move_to(x, y);
}
/*
* Ignore this keystroke.
*/
I()
{
}
/*
* Leave editor. If the file has changed, ask if the user wants to save it.
*/
XT()
{
if (modified == TRUE && ask_save() == ERRORS)
return;
raw_mode(OFF);
set_cursor(0, YMAX);
putchar('\n');
flush();
(void) unlink(yank_file); /* Might not be necessary */
exit(0);
}
/*
* ESC() prompts for a count and wants a command after that. It repeats the
* command count times. If a ^\ is given during repeating, stop looping and
* return to main loop.
*/
ESC()
{
register int count;
register int (*func)();
int index, number;
extern int (*key_map[])(), I();
if ((index = get_number("Please enter repeat count.", &number)) == ERRORS)
return;
if ((func = key_map[index]) == I) { /* Function assigned? */
clear_status();
return;
}
count = number;
while (count-- > 0 && quit == FALSE) {
if (stat_visible == TRUE)
clear_status();
(*func)(index);
flush();
}
if (quit == TRUE) /* Abort has been given */
error("Aborted", NIL_PTR);
else
clear_status();
}
/*
* Ask the user if he wants to save his file or not.
*/
ask_save()
{
register int c;
status_line(file_name[0] ? basename(file_name) : "[buffer]" ,
" has been modified. Save? (y/n)");
while((c = getchar()) != 'y' && c != 'n' && quit == FALSE) {
ring_bell();
flush();
}
clear_status();
if (c == 'y')
return WT();
if (c == 'n')
return FINE;
quit = FALSE; /* Abort character has been given */
return ERRORS;
}
/*
* Line_number() finds the line number we're on.
*/
line_number()
{
register LINE *line = header->next;
register int count = 1;
while (line != cur_line) {
count++;
line = line->next;
}
return count;
}
/*
* Display a line telling how many chars and lines the file contains. Also tell
* whether the file is readonly and/or modified.
*/
file_status(message, count, file, lines, writefl, changed)
char *message;
register long count; /* Contains number of characters in file */
char *file;
int lines;
FLAG writefl, changed;
{
register LINE *line;
char msg[LINE_LEN + 40];/* Buffer to hold line */
char yank_msg[LINE_LEN];/* Buffer for msg of yank_file */
if (count < 0) /* Not valid. Count chars in file */
for (line = header->next; line != tail; line = line->next)
count += length_of(line->text);
if (yank_status != NOT_VALID) /* Append buffer info */
build_string(yank_msg, " Buffer: %D char%s.", chars_saved,
(chars_saved == 1L) ? "" : "s");
else
yank_msg[0] = '\0';
build_string(msg, "%s %s%s%s %d line%s %D char%s.%s Line %d", message,
(rpipe == TRUE && *message != '[') ? "standard input" : basename(file),
(changed == TRUE) ? "*" : "",
(writefl == FALSE) ? " (Readonly)" : "",
lines, (lines == 1) ? "" : "s",
count, (count == 1L) ? "" : "s",
yank_msg, line_number());
if (length_of(msg) + 1 > LINE_LEN - 4) {
msg[LINE_LEN - 4] = SHIFT_MARK; /* Overflow on status line */
msg[LINE_LEN - 3] = '\0';
}
status_line(msg, NIL_PTR); /* Print the information */
}
/*
* Build_string() prints the arguments as described in fmt, into the buffer.
* %s indicates an argument string, %d indicated an argument number.
*/
/* VARARGS */
build_string(buf, fmt, args)
register char *buf, *fmt;
int args;
{
int *argptr = &args;
char *scanp;
while (*fmt) {
if (*fmt == '%') {
fmt++;
switch (*fmt++) {
case 's' :
scanp = (char *) *argptr;
break;
case 'd' :
scanp = num_out((long) *argptr);
break;
case 'D' :
scanp = num_out((long) *((long *)
#ifdef UNIX
argptr));
#else
argptr++));
#endif UNIX
break;
default :
scanp = "";
}
while (*buf++ = *scanp++)
;
buf--;
argptr++;
}
else
*buf++ = *fmt++;
}
*buf = '\0';
}
/*
* Output an (unsigned) long in a 10 digit field without leading zeros.
* It returns a pointer to the first digit in the buffer.
*/
char *num_out(number)
long number;
{
static char num_buf[11]; /* Buffer to build number */
register long digit; /* Next digit of number */
register long pow = 1000000000L; /* Highest ten power of long */
FLAG digit_seen = FALSE;
int i;
for (i = 0; i < 10; i++) {
digit = number / pow; /* Get next digit */
if (digit == 0L && digit_seen == FALSE && i != 9)
num_buf[i] = ' ';
else {
num_buf[i] = '0' + (char) digit;
number -= digit * pow; /* Erase digit */
digit_seen = TRUE;
}
pow /= 10L; /* Get next digit */
}
for (i = 0; num_buf[i] == ' '; i++) /* Skip leading spaces */
;
return (&num_buf[i]);
}
/*
* Get_number() read a number from the terminal. The last character typed in is
* returned. ERRORS is returned on a bad number. The resulting number is put
* into the integer the arguments points to.
*/
get_number(message, result)
char *message;
int *result;
{
register int index;
register int count = 0;
status_line(message, NIL_PTR);
index = getchar();
if (quit == FALSE && (index < '0' || index > '9')) {
error("Bad count", NIL_PTR);
return ERRORS;
}
/* Convert input to a decimal number */
while (index >= '0' && index <= '9' && quit == FALSE) {
count *= 10;
count += index - '0';
index = getchar();
}
if (quit == TRUE) {
clear_status();
return ERRORS;
}
*result = count;
return index;
}
/*
* Input() reads a string from the terminal. When the KILL character is typed,
* it returns ERRORS.
*/
input(inbuf, clearfl)
char *inbuf;
FLAG clearfl;
{
register char *ptr;
register char c; /* Character read */
ptr = inbuf;
*ptr = '\0';
while (quit == FALSE) {
flush();
switch (c = getchar()) {
case '\b' : /* Erase previous char */
if (ptr > inbuf) {
ptr--;
#ifdef UNIX
tputs(SE, 0, _putchar);
#else
string_print(normal_video);
#endif UNIX
if (is_tab(*ptr))
string_print(" \b\b\b \b\b");
else
string_print(" \b\b \b");
#ifdef UNIX
tputs(SO, 0, _putchar);
#else
string_print(rev_video);
#endif UNIX
string_print(" \b");
*ptr = '\0';
}
else
ring_bell();
break;
case '\n' : /* End of input */
/* If inbuf is empty clear status_line */
return (ptr == inbuf && clearfl == TRUE) ? NO_INPUT :FINE;
default : /* Only read ASCII chars */
if ((c >= ' ' && c <= '~') || c == '\t') {
*ptr++ = c;
*ptr = '\0';
if (c == '\t')
string_print("^I");
else
putchar(c);
string_print(" \b");
}
else
ring_bell();
}
}
quit = FALSE;
return ERRORS;
}
/*
* Get_file() reads a filename from the terminal. Filenames longer than
* FILE_LENGHT chars are truncated.
*/
get_file(message, file)
char *message, *file;
{
char *ptr;
int ret;
if (message == NIL_PTR || (ret = get_string(message, file, TRUE)) == FINE) {
if (length_of((ptr = basename(file))) > FILE_LENGTH)
ptr[FILE_LENGTH] = '\0';
}
return ret;
}
/* ======================================================================== *
* UNIX I/O Routines *
* ======================================================================== */
#ifdef UNIX
#undef putchar
_getchar()
{
char c;
if (read(input_fd, &c, 1) != 1 && quit == FALSE)
panic ("Cannot read 1 byte from input");
return c & 0177;
}
_flush()
{
(void) fflush(stdout);
}
_putchar(c)
char c;
{
(void) write_char(STD_OUT, c);
}
get_term()
{
static char termbuf[50];
extern char *tgetstr(), *getenv();
char *loc = termbuf;
char entry[1024];
if (tgetent(entry, getenv("TERM")) <= 0) {
printf("Unknown terminal.\n");
exit(1);
}
AL = tgetstr("al", &loc);
CE = tgetstr("ce", &loc);
VS = tgetstr("vs", &loc);
CL = tgetstr("cl", &loc);
SO = tgetstr("so", &loc);
SE = tgetstr("se", &loc);
CM = tgetstr("cm", &loc);
if (!CE || !SO || !SE || !CL || !AL || !CM) {
printf("Sorry, no mined on this type of terminal\n");
exit(1);
}
}
#endif UNIX