← Commit list

5ea50697f

Denys Vlasenko

2017-07-27

SUCCESS Duration: 142s

Subject

ed: fix --help and reorder functions, no code changes

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

editors/ed.c +741 -773

editors/ed.c+741 -773

@@ -6,7 +6,6 @@
	*
	* The "ed" built-in command (much simplified)
	*/
-
	//config:config ED
	//config: bool "ed (25 kb)"
	//config: default y
@@ -19,7 +18,7 @@

	//applet:IF_ED(APPLET(ed, BB_DIR_BIN, BB_SUID_DROP))

-	//usage:#define ed_trivial_usage ""
+	//usage:#define ed_trivial_usage "[FILE]"
	//usage:#define ed_full_usage ""

	#include "libbb.h"
@@ -32,7 +31,6 @@ typedef struct LINE {
	char data[1];
	} LINE;

-
	#define searchString bb_common_bufsiz1

	enum {
@@ -71,22 +69,6 @@ struct globals {
	SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
	} while (0)

-
-	static void doCommands(void);
-	static void subCommand(const char *cmd, int num1, int num2);
-	static int getNum(const char *retcp, smallint retHaveNum, int *retNum);
-	static int setCurNum(int num);
-	static void addLines(int num);
-	static int insertLine(int num, const char *data, int len);
-	static void deleteLines(int num1, int num2);
-	static int printLines(int num1, int num2, int expandFlag);
-	static int writeLines(const char *file, int num1, int num2);
-	static int readLines(const char *file, int num);
-	static int searchLines(const char *str, int num1, int num2);
-	static LINE *findLine(int num);
-	static int findString(const LINE lp, const char str, int len, int offset);
-
-
	static int bad_nums(int num1, int num2, const char *for_what)
	{
	if ((num1 < 1) \|\| (num2 > lastNum) \|\| (num1 > num2)) {
@@ -96,7 +78,6 @@ static int bad_nums(int num1, int num2, const char *for_what)
	return 0;
	}

-
	static char skip_blank(const char cp)
	{
	while (isblank(*cp))
@@ -104,949 +85,936 @@ static char skip_blank(const char cp)
	return (char *)cp;
	}

-
-	int ed_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-	int ed_main(int argc UNUSED_PARAM, char **argv)
+	/*
+	* Return a pointer to the specified line number.
+	*/
+	static LINE *findLine(int num)
	{
-	INIT_G();
+	LINE *lp;
+	int lnum;

-	bufSize = INITBUF_SIZE;
-	bufBase = xmalloc(bufSize);
-	bufPtr = bufBase;
-	lines.next = &lines;
-	lines.prev = &lines;
+	if ((num < 1) \|\| (num > lastNum)) {
+	bb_error_msg("line number %d does not exist", num);
+	return NULL;
+	}

-	if (argv[1]) {
-	fileName = xstrdup(argv[1]);
-	if (!readLines(fileName, 1)) {
-	return EXIT_SUCCESS;
-	}
-	if (lastNum)
-	setCurNum(1);
-	dirty = FALSE;
+	if (curNum <= 0) {
+	curNum = 1;
+	curLine = lines.next;
	}

-	doCommands();
-	return EXIT_SUCCESS;
+	if (num == curNum)
+	return curLine;
+
+	lp = curLine;
+	lnum = curNum;
+	if (num < (curNum / 2)) {
+	lp = lines.next;
+	lnum = 1;
+	} else if (num > ((curNum + lastNum) / 2)) {
+	lp = lines.prev;
+	lnum = lastNum;
+	}
+
+	while (lnum < num) {
+	lp = lp->next;
+	lnum++;
+	}
+
+	while (lnum > num) {
+	lp = lp->prev;
+	lnum--;
+	}
+	return lp;
	}

	/*
-	* Read commands until we are told to stop.
+	* Search a line for the specified string starting at the specified
+	* offset in the line. Returns the offset of the found string, or -1.
	*/
-	static void doCommands(void)
+	static int findString(const LINE lp, const char str, int len, int offset)
	{
-	const char *cp;
-	char *endbuf, buf[USERSIZE];
-	int len, num1, num2;
-	smallint have1, have2;
+	int left;
+	const char cp, ncp;

-	while (TRUE) {
-	/* Returns:
-	* -1 on read errors or EOF, or on bare Ctrl-D.
-	* 0 on ctrl-C,
-	* >0 length of input string, including terminating '\n'
-	*/
-	len = read_line_input(NULL, ": ", buf, sizeof(buf), /timeout/ -1);
-	if (len <= 0)
-	return;
-	endbuf = &buf[len - 1];
-	while ((endbuf > buf) && isblank(endbuf[-1]))
-	endbuf--;
-	*endbuf = '\0';
+	cp = &lp->data[offset];
+	left = lp->len - offset;

-	cp = skip_blank(buf);
-	have1 = FALSE;
-	have2 = FALSE;
+	while (left >= len) {
+	ncp = memchr(cp, *str, left);
+	if (ncp == NULL)
+	return -1;
+	left -= (ncp - cp);
+	if (left < len)
+	return -1;
+	cp = ncp;
+	if (memcmp(cp, str, len) == 0)
+	return (cp - lp->data);
+	cp++;
+	left--;
+	}

-	if ((curNum == 0) && (lastNum > 0)) {
-	curNum = 1;
-	curLine = lines.next;
-	}
+	return -1;
+	}

-	if (!getNum(&cp, &have1, &num1))
-	continue;
+	/*
+	* Search for a line which contains the specified string.
+	* If the string is "", then the previously searched for string
+	* is used. The currently searched for string is saved for future use.
+	* Returns the line number which matches, or 0 if there was no match
+	* with an error printed.
+	*/
+	static NOINLINE int searchLines(const char *str, int num1, int num2)
+	{
+	const LINE *lp;
+	int len;

-	cp = skip_blank(cp);
+	if (bad_nums(num1, num2, "search"))
+	return 0;

-	if (*cp == ',') {
-	cp++;
-	if (!getNum(&cp, &have2, &num2))
-	continue;
-	if (!have1)
-	num1 = 1;
-	if (!have2)
-	num2 = lastNum;
-	have1 = TRUE;
-	have2 = TRUE;
+	if (*str == '\0') {
+	if (searchString[0] == '\0') {
+	bb_error_msg("no previous search string");
+	return 0;
	}
-	if (!have1)
-	num1 = curNum;
-	if (!have2)
-	num2 = num1;
+	str = searchString;
+	}

-	switch (*cp++) {
-	case 'a':
-	addLines(num1 + 1);
-	break;
+	if (str != searchString)
+	strcpy(searchString, str);

-	case 'c':
-	deleteLines(num1, num2);
-	addLines(num1);
-	break;
+	len = strlen(str);

-	case 'd':
-	deleteLines(num1, num2);
-	break;
+	lp = findLine(num1);
+	if (lp == NULL)
+	return 0;

-	case 'f':
-	if (cp && !isblank(cp)) {
-	bb_error_msg("bad file command");
-	break;
-	}
-	cp = skip_blank(cp);
-	if (*cp == '\0') {
-	if (fileName)
-	printf("\"%s\"\n", fileName);
-	else
-	puts("No file name");
-	break;
-	}
-	free(fileName);
-	fileName = xstrdup(cp);
-	break;
+	while (num1 <= num2) {
+	if (findString(lp, str, len, 0) >= 0)
+	return num1;
+	num1++;
+	lp = lp->next;
+	}

-	case 'i':
-	addLines(num1);
-	break;
+	bb_error_msg("can't find string \"%s\"", str);
+	return 0;
+	}

-	case 'k':
-	cp = skip_blank(cp);
-	if ((cp < 'a') \|\| (cp > 'z') \|\| cp[1]) {
-	bb_error_msg("bad mark name");
-	break;
-	}
-	marks[*cp - 'a'] = num2;
-	break;
+	/*
+	* Parse a line number argument if it is present. This is a sum
+	* or difference of numbers, '.', '$', 'x, or a search string.
+	* Returns TRUE if successful (whether or not there was a number).
+	* Returns FALSE if there was a parsing error, with a message output.
+	* Whether there was a number is returned indirectly, as is the number.
+	* The character pointer which stopped the scan is also returned.
+	*/
+	static int getNum(const char *retcp, smallint retHaveNum, int *retNum)
+	{
+	const char *cp;
+	char *endStr, str[USERSIZE];
+	int value, num;
+	smallint haveNum, minus;

-	case 'l':
-	printLines(num1, num2, TRUE);
-	break;
+	cp = *retcp;
+	value = 0;
+	haveNum = FALSE;
+	minus = 0;

-	case 'p':
-	printLines(num1, num2, FALSE);
-	break;
+	while (TRUE) {
+	cp = skip_blank(cp);

-	case 'q':
-	cp = skip_blank(cp);
-	if (have1 \|\| *cp) {
-	bb_error_msg("bad quit command");
+	switch (*cp) {
+	case '.':
+	haveNum = TRUE;
+	num = curNum;
+	cp++;
	break;
-	}
-	if (!dirty)
-	return;
-	len = read_line_input(NULL, "Really quit? ", buf, 16, /timeout/ -1);
-	/* read error/EOF - no way to continue */
-	if (len < 0)
-	return;
-	cp = skip_blank(buf);
-	if ((cp \| 0x20) == 'y') / Y or y */
-	return;
-	break;

-	case 'r':
-	if (cp && !isblank(cp)) {
-	bb_error_msg("bad read command");
-	break;
-	}
-	cp = skip_blank(cp);
-	if (*cp == '\0') {
-	bb_error_msg("no file name");
+	case '$':
+	haveNum = TRUE;
+	num = lastNum;
+	cp++;
	break;
-	}
-	if (!have1)
-	num1 = lastNum;
-	if (readLines(cp, num1 + 1))
-	break;
-	if (fileName == NULL)
-	fileName = xstrdup(cp);
-	break;

-	case 's':
-	subCommand(cp, num1, num2);
-	break;
-
-	case 'w':
-	if (cp && !isblank(cp)) {
-	bb_error_msg("bad write command");
-	break;
-	}
-	cp = skip_blank(cp);
-	if (!have1) {
-	num1 = 1;
-	num2 = lastNum;
-	}
-	if (*cp == '\0')
-	cp = fileName;
-	if (cp == NULL) {
-	bb_error_msg("no file name specified");
+	case '\'':
+	cp++;
+	if ((cp < 'a') \|\| (cp > 'z')) {
+	bb_error_msg("bad mark name");
+	return FALSE;
+	}
+	haveNum = TRUE;
+	num = marks[*cp++ - 'a'];
	break;
-	}
-	writeLines(cp, num1, num2);
-	break;

-	case 'z':
-	switch (*cp) {
-	case '-':
-	printLines(curNum - 21, curNum, FALSE);
-	break;
-	case '.':
-	printLines(curNum - 11, curNum + 10, FALSE);
+	case '/':
+	strcpy(str, ++cp);
+	endStr = strchr(str, '/');
+	if (endStr) {
+	*endStr++ = '\0';
+	cp += (endStr - str);
+	} else
+	cp = "";
+	num = searchLines(str, curNum, lastNum);
+	if (num == 0)
+	return FALSE;
+	haveNum = TRUE;
	break;
+
	default:
-	printLines(curNum, curNum + 21, FALSE);
+	if (!isdigit(*cp)) {
+	*retcp = cp;
+	*retHaveNum = haveNum;
+	*retNum = value;
+	return TRUE;
+	}
+	num = 0;
+	while (isdigit(*cp))
+	num = num * 10 + *cp++ - '0';
+	haveNum = TRUE;
	break;
-	}
-	break;
+	}

-	case '.':
-	if (have1) {
-	bb_error_msg("no arguments allowed");
-	break;
-	}
-	printLines(curNum, curNum, FALSE);
-	break;
+	value += (minus ? -num : num);

-	case '-':
-	if (setCurNum(curNum - 1))
-	printLines(curNum, curNum, FALSE);
-	break;
+	cp = skip_blank(cp);

-	case '=':
-	printf("%d\n", num1);
-	break;
-	case '\0':
-	if (have1) {
-	printLines(num2, num2, FALSE);
+	switch (*cp) {
+	case '-':
+	minus = 1;
+	cp++;
	break;
-	}
-	if (setCurNum(curNum + 1))
-	printLines(curNum, curNum, FALSE);
-	break;

-	default:
-	bb_error_msg("unimplemented command");
-	break;
+	case '+':
+	minus = 0;
+	cp++;
+	break;
+
+	default:
+	*retcp = cp;
+	*retHaveNum = haveNum;
+	*retNum = value;
+	return TRUE;
	}
	}
	}

-
	/*
-	* Do the substitute command.
-	* The current line is set to the last substitution done.
+	* Set the current line number.
+	* Returns TRUE if successful.
	*/
-	static void subCommand(const char *cmd, int num1, int num2)
+	static int setCurNum(int num)
	{
-	char cp, oldStr, *newStr, buf[USERSIZE];
-	int delim, oldLen, newLen, deltaLen, offset;
-	LINE lp, nlp;
-	int globalFlag, printFlag, didSub, needPrint;
-
-	if (bad_nums(num1, num2, "substitute"))
-	return;
+	LINE *lp;

-	globalFlag = FALSE;
-	printFlag = FALSE;
-	didSub = FALSE;
-	needPrint = FALSE;
+	lp = findLine(num);
+	if (lp == NULL)
+	return FALSE;
+	curNum = num;
+	curLine = lp;
+	return TRUE;
+	}

-	/*
-	* Copy the command so we can modify it.
-	*/
-	strcpy(buf, cmd);
-	cp = buf;
+	/*
+	* Insert a new line with the specified text.
+	* The line is inserted so as to become the specified line,
+	* thus pushing any existing and further lines down one.
+	* The inserted line is also set to become the current line.
+	* Returns TRUE if successful.
+	*/
+	static int insertLine(int num, const char *data, int len)
+	{
+	LINE newLp, lp;

-	if (isblank(cp) \|\| (cp == '\0')) {
-	bb_error_msg("bad delimiter for substitute");
-	return;
+	if ((num < 1) \|\| (num > lastNum + 1)) {
+	bb_error_msg("inserting at bad line number");
+	return FALSE;
	}

-	delim = *cp++;
-	oldStr = cp;
+	newLp = xmalloc(sizeof(LINE) + len - 1);

-	cp = strchr(cp, delim);
-	if (cp == NULL) {
-	bb_error_msg("missing 2nd delimiter for substitute");
-	return;
-	}
+	memcpy(newLp->data, data, len);
+	newLp->len = len;

-	*cp++ = '\0';
+	if (num > lastNum)
+	lp = &lines;
+	else {
+	lp = findLine(num);
+	if (lp == NULL) {
+	free((char *) newLp);
+	return FALSE;
+	}
+	}

-	newStr = cp;
-	cp = strchr(cp, delim);
+	newLp->next = lp;
+	newLp->prev = lp->prev;
+	lp->prev->next = newLp;
+	lp->prev = newLp;

-	if (cp)
-	*cp++ = '\0';
-	else
-	cp = (char*)"";
+	lastNum++;
+	dirty = TRUE;
+	return setCurNum(num);
+	}

-	while (cp) switch (cp++) {
-	case 'g':
-	globalFlag = TRUE;
-	break;
-	case 'p':
-	printFlag = TRUE;
-	break;
-	default:
-	bb_error_msg("unknown option for substitute");
-	return;
-	}
+	/*
+	* Add lines which are typed in by the user.
+	* The lines are inserted just before the specified line number.
+	* The lines are terminated by a line containing a single dot (ugly!),
+	* or by an end of file.
+	*/
+	static void addLines(int num)
+	{
+	int len;
+	char buf[USERSIZE + 1];

-	if (*oldStr == '\0') {
-	if (searchString[0] == '\0') {
-	bb_error_msg("no previous search string");
+	while (1) {
+	/* Returns:
+	* -1 on read errors or EOF, or on bare Ctrl-D.
+	* 0 on ctrl-C,
+	* >0 length of input string, including terminating '\n'
+	*/
+	len = read_line_input(NULL, "", buf, sizeof(buf), /timeout/ -1);
+	if (len <= 0) {
+	/* Previously, ctrl-C was exiting to shell.
+	* Now we exit to ed prompt. Is in important? */
	return;
	}
-	oldStr = searchString;
+	if ((buf[0] == '.') && (buf[1] == '\n') && (buf[2] == '\0'))
+	return;
+	if (!insertLine(num++, buf, len))
+	return;
	}
+	}

-	if (oldStr != searchString)
-	strcpy(searchString, oldStr);
-
-	lp = findLine(num1);
-	if (lp == NULL)
-	return;
+	/*
+	* Read lines from a file at the specified line number.
+	* Returns TRUE if the file was successfully read.
+	*/
+	static int readLines(const char *file, int num)
+	{
+	int fd, cc;
+	int len, lineCount, charCount;
+	char *cp;

-	oldLen = strlen(oldStr);
-	newLen = strlen(newStr);
-	deltaLen = newLen - oldLen;
-	offset = 0;
-	nlp = NULL;
+	if ((num < 1) \|\| (num > lastNum + 1)) {
+	bb_error_msg("bad line for read");
+	return FALSE;
+	}

-	while (num1 <= num2) {
-	offset = findString(lp, oldStr, oldLen, offset);
+	fd = open(file, 0);
+	if (fd < 0) {
+	bb_simple_perror_msg(file);
+	return FALSE;
+	}

-	if (offset < 0) {
-	if (needPrint) {
-	printLines(num1, num1, FALSE);
-	needPrint = FALSE;
-	}
-	offset = 0;
-	lp = lp->next;
-	num1++;
-	continue;
-	}
+	bufPtr = bufBase;
+	bufUsed = 0;
+	lineCount = 0;
+	charCount = 0;
+	cc = 0;

-	needPrint = printFlag;
-	didSub = TRUE;
-	dirty = TRUE;
+	printf("\"%s\", ", file);
+	fflush_all();

-	/*
-	* If the replacement string is the same size or shorter
-	* than the old string, then the substitution is easy.
-	*/
-	if (deltaLen <= 0) {
-	memcpy(&lp->data[offset], newStr, newLen);
-	if (deltaLen) {
-	memcpy(&lp->data[offset + newLen],
-	&lp->data[offset + oldLen],
-	lp->len - offset - oldLen);
+	do {
+	cp = memchr(bufPtr, '\n', bufUsed);

-	lp->len += deltaLen;
-	}
-	offset += newLen;
-	if (globalFlag)
-	continue;
-	if (needPrint) {
-	printLines(num1, num1, FALSE);
-	needPrint = FALSE;
+	if (cp) {
+	len = (cp - bufPtr) + 1;
+	if (!insertLine(num, bufPtr, len)) {
+	close(fd);
+	return FALSE;
	}
-	lp = lp->next;
-	num1++;
+	bufPtr += len;
+	bufUsed -= len;
+	charCount += len;
+	lineCount++;
+	num++;
	continue;
	}

-	/*
-	* The new string is larger, so allocate a new line
-	* structure and use that. Link it in place of
-	* the old line structure.
-	*/
-	nlp = xmalloc(sizeof(LINE) + lp->len + deltaLen);
-
-	nlp->len = lp->len + deltaLen;
-
-	memcpy(nlp->data, lp->data, offset);
-	memcpy(&nlp->data[offset], newStr, newLen);
-	memcpy(&nlp->data[offset + newLen],
-	&lp->data[offset + oldLen],
-	lp->len - offset - oldLen);
-
-	nlp->next = lp->next;
-	nlp->prev = lp->prev;
-	nlp->prev->next = nlp;
-	nlp->next->prev = nlp;
-
-	if (curLine == lp)
-	curLine = nlp;
+	if (bufPtr != bufBase) {
+	memcpy(bufBase, bufPtr, bufUsed);
+	bufPtr = bufBase + bufUsed;
+	}

-	free(lp);
-	lp = nlp;
+	if (bufUsed >= bufSize) {
+	len = (bufSize * 3) / 2;
+	cp = xrealloc(bufBase, len);
+	bufBase = cp;
+	bufPtr = bufBase + bufUsed;
+	bufSize = len;
+	}

-	offset += newLen;
+	cc = safe_read(fd, bufPtr, bufSize - bufUsed);
+	bufUsed += cc;
+	bufPtr = bufBase;
+	} while (cc > 0);

-	if (globalFlag)
-	continue;
+	if (cc < 0) {
+	bb_simple_perror_msg(file);
+	close(fd);
+	return FALSE;
+	}

-	if (needPrint) {
-	printLines(num1, num1, FALSE);
-	needPrint = FALSE;
+	if (bufUsed) {
+	if (!insertLine(num, bufPtr, bufUsed)) {
+	close(fd);
+	return -1;
	}
-
-	lp = lp->next;
-	num1++;
+	lineCount++;
+	charCount += bufUsed;
	}

-	if (!didSub)
-	bb_error_msg("no substitutions found for \"%s\"", oldStr);
-	}
+	close(fd);
+
+	printf("%d lines%s, %d chars\n", lineCount,
+	(bufUsed ? " (incomplete)" : ""), charCount);

+	return TRUE;
+	}

	/*
-	* Search a line for the specified string starting at the specified
-	* offset in the line. Returns the offset of the found string, or -1.
+	* Write the specified lines out to the specified file.
+	* Returns TRUE if successful, or FALSE on an error with a message output.
	*/
-	static int findString(const LINE lp, const char str, int len, int offset)
+	static int writeLines(const char *file, int num1, int num2)
	{
-	int left;
-	const char cp, ncp;
+	LINE *lp;
+	int fd, lineCount, charCount;

-	cp = &lp->data[offset];
-	left = lp->len - offset;
+	if (bad_nums(num1, num2, "write"))
+	return FALSE;

-	while (left >= len) {
-	ncp = memchr(cp, *str, left);
-	if (ncp == NULL)
-	return -1;
-	left -= (ncp - cp);
-	if (left < len)
-	return -1;
-	cp = ncp;
-	if (memcmp(cp, str, len) == 0)
-	return (cp - lp->data);
-	cp++;
-	left--;
-	}
+	lineCount = 0;
+	charCount = 0;

-	return -1;
-	}
+	fd = creat(file, 0666);
+	if (fd < 0) {
+	bb_simple_perror_msg(file);
+	return FALSE;
+	}

+	printf("\"%s\", ", file);
+	fflush_all();

-	/*
-	* Add lines which are typed in by the user.
-	* The lines are inserted just before the specified line number.
-	* The lines are terminated by a line containing a single dot (ugly!),
-	* or by an end of file.
-	*/
-	static void addLines(int num)
-	{
-	int len;
-	char buf[USERSIZE + 1];
+	lp = findLine(num1);
+	if (lp == NULL) {
+	close(fd);
+	return FALSE;
+	}

-	while (1) {
-	/* Returns:
-	* -1 on read errors or EOF, or on bare Ctrl-D.
-	* 0 on ctrl-C,
-	* >0 length of input string, including terminating '\n'
-	*/
-	len = read_line_input(NULL, "", buf, sizeof(buf), /timeout/ -1);
-	if (len <= 0) {
-	/* Previously, ctrl-C was exiting to shell.
-	* Now we exit to ed prompt. Is in important? */
-	return;
+	while (num1++ <= num2) {
+	if (full_write(fd, lp->data, lp->len) != lp->len) {
+	bb_simple_perror_msg(file);
+	close(fd);
+	return FALSE;
	}
-	if ((buf[0] == '.') && (buf[1] == '\n') && (buf[2] == '\0'))
-	return;
-	if (!insertLine(num++, buf, len))
-	return;
+	charCount += lp->len;
+	lineCount++;
+	lp = lp->next;
+	}
+
+	if (close(fd) < 0) {
+	bb_simple_perror_msg(file);
+	return FALSE;
	}
-	}

+	printf("%d lines, %d chars\n", lineCount, charCount);
+	return TRUE;
+	}

	/*
-	* Parse a line number argument if it is present. This is a sum
-	* or difference of numbers, '.', '$', 'x, or a search string.
-	* Returns TRUE if successful (whether or not there was a number).
-	* Returns FALSE if there was a parsing error, with a message output.
-	* Whether there was a number is returned indirectly, as is the number.
-	* The character pointer which stopped the scan is also returned.
+	* Print lines in a specified range.
+	* The last line printed becomes the current line.
+	* If expandFlag is TRUE, then the line is printed specially to
+	* show magic characters.
	*/
-	static int getNum(const char *retcp, smallint retHaveNum, int *retNum)
+	static int printLines(int num1, int num2, int expandFlag)
	{
+	const LINE *lp;
	const char *cp;
-	char *endStr, str[USERSIZE];
-	int value, num;
-	smallint haveNum, minus;
+	int ch, count;

-	cp = *retcp;
-	value = 0;
-	haveNum = FALSE;
-	minus = 0;
+	if (bad_nums(num1, num2, "print"))
+	return FALSE;

-	while (TRUE) {
-	cp = skip_blank(cp);
+	lp = findLine(num1);
+	if (lp == NULL)
+	return FALSE;

-	switch (*cp) {
-	case '.':
-	haveNum = TRUE;
-	num = curNum;
-	cp++;
-	break;
+	while (num1 <= num2) {
+	if (!expandFlag) {
+	write(STDOUT_FILENO, lp->data, lp->len);
+	setCurNum(num1++);
+	lp = lp->next;
+	continue;
+	}

-	case '$':
-	haveNum = TRUE;
-	num = lastNum;
-	cp++;
-	break;
-
-	case '\'':
-	cp++;
-	if ((cp < 'a') \|\| (cp > 'z')) {
-	bb_error_msg("bad mark name");
-	return FALSE;
-	}
-	haveNum = TRUE;
-	num = marks[*cp++ - 'a'];
-	break;
+	/*
+	* Show control characters and characters with the
+	* high bit set specially.
+	*/
+	cp = lp->data;
+	count = lp->len;

-	case '/':
-	strcpy(str, ++cp);
-	endStr = strchr(str, '/');
-	if (endStr) {
-	*endStr++ = '\0';
-	cp += (endStr - str);
-	} else
-	cp = "";
-	num = searchLines(str, curNum, lastNum);
-	if (num == 0)
-	return FALSE;
-	haveNum = TRUE;
-	break;
+	if ((count > 0) && (cp[count - 1] == '\n'))
+	count--;

-	default:
-	if (!isdigit(*cp)) {
-	*retcp = cp;
-	*retHaveNum = haveNum;
-	*retNum = value;
-	return TRUE;
-	}
-	num = 0;
-	while (isdigit(*cp))
-	num = num * 10 + *cp++ - '0';
-	haveNum = TRUE;
-	break;
+	while (count-- > 0) {
+	ch = (unsigned char) *cp++;
+	fputc_printable(ch \| PRINTABLE_META, stdout);
	}

-	value += (minus ? -num : num);
-
-	cp = skip_blank(cp);
-
-	switch (*cp) {
-	case '-':
-	minus = 1;
-	cp++;
-	break;
-
-	case '+':
-	minus = 0;
-	cp++;
-	break;
+	fputs("$\n", stdout);

-	default:
-	*retcp = cp;
-	*retHaveNum = haveNum;
-	*retNum = value;
-	return TRUE;
-	}
+	setCurNum(num1++);
+	lp = lp->next;
	}
-	}

+	return TRUE;
+	}

	/*
-	* Read lines from a file at the specified line number.
-	* Returns TRUE if the file was successfully read.
+	* Delete lines from the given range.
	*/
-	static int readLines(const char *file, int num)
+	static void deleteLines(int num1, int num2)
	{
-	int fd, cc;
-	int len, lineCount, charCount;
-	char *cp;
+	LINE lp, nlp, *plp;
+	int count;

-	if ((num < 1) \|\| (num > lastNum + 1)) {
-	bb_error_msg("bad line for read");
-	return FALSE;
-	}
+	if (bad_nums(num1, num2, "delete"))
+	return;

-	fd = open(file, 0);
-	if (fd < 0) {
-	bb_simple_perror_msg(file);
-	return FALSE;
-	}
+	lp = findLine(num1);
+	if (lp == NULL)
+	return;

-	bufPtr = bufBase;
-	bufUsed = 0;
-	lineCount = 0;
-	charCount = 0;
-	cc = 0;
+	if ((curNum >= num1) && (curNum <= num2)) {
+	if (num2 < lastNum)
+	setCurNum(num2 + 1);
+	else if (num1 > 1)
+	setCurNum(num1 - 1);
+	else
+	curNum = 0;
+	}

-	printf("\"%s\", ", file);
-	fflush_all();
+	count = num2 - num1 + 1;
+	if (curNum > num2)
+	curNum -= count;
+	lastNum -= count;

-	do {
-	cp = memchr(bufPtr, '\n', bufUsed);
+	while (count-- > 0) {
+	nlp = lp->next;
+	plp = lp->prev;
+	plp->next = nlp;
+	nlp->prev = plp;
+	free(lp);
+	lp = nlp;
+	}

-	if (cp) {
-	len = (cp - bufPtr) + 1;
-	if (!insertLine(num, bufPtr, len)) {
-	close(fd);
-	return FALSE;
-	}
-	bufPtr += len;
-	bufUsed -= len;
-	charCount += len;
-	lineCount++;
-	num++;
-	continue;
-	}
+	dirty = TRUE;
+	}

-	if (bufPtr != bufBase) {
-	memcpy(bufBase, bufPtr, bufUsed);
-	bufPtr = bufBase + bufUsed;
-	}
+	/*
+	* Do the substitute command.
+	* The current line is set to the last substitution done.
+	*/
+	static void subCommand(const char *cmd, int num1, int num2)
+	{
+	char cp, oldStr, *newStr, buf[USERSIZE];
+	int delim, oldLen, newLen, deltaLen, offset;
+	LINE lp, nlp;
+	int globalFlag, printFlag, didSub, needPrint;

-	if (bufUsed >= bufSize) {
-	len = (bufSize * 3) / 2;
-	cp = xrealloc(bufBase, len);
-	bufBase = cp;
-	bufPtr = bufBase + bufUsed;
-	bufSize = len;
-	}
+	if (bad_nums(num1, num2, "substitute"))
+	return;

-	cc = safe_read(fd, bufPtr, bufSize - bufUsed);
-	bufUsed += cc;
-	bufPtr = bufBase;
-	} while (cc > 0);
+	globalFlag = FALSE;
+	printFlag = FALSE;
+	didSub = FALSE;
+	needPrint = FALSE;

-	if (cc < 0) {
-	bb_simple_perror_msg(file);
-	close(fd);
-	return FALSE;
-	}
+	/*
+	* Copy the command so we can modify it.
+	*/
+	strcpy(buf, cmd);
+	cp = buf;

-	if (bufUsed) {
-	if (!insertLine(num, bufPtr, bufUsed)) {
-	close(fd);
-	return -1;
-	}
-	lineCount++;
-	charCount += bufUsed;
+	if (isblank(cp) \|\| (cp == '\0')) {
+	bb_error_msg("bad delimiter for substitute");
+	return;
	}

-	close(fd);
-
-	printf("%d lines%s, %d chars\n", lineCount,
-	(bufUsed ? " (incomplete)" : ""), charCount);
+	delim = *cp++;
+	oldStr = cp;

-	return TRUE;
-	}
+	cp = strchr(cp, delim);
+	if (cp == NULL) {
+	bb_error_msg("missing 2nd delimiter for substitute");
+	return;
+	}

+	*cp++ = '\0';

-	/*
-	* Write the specified lines out to the specified file.
-	* Returns TRUE if successful, or FALSE on an error with a message output.
-	*/
-	static int writeLines(const char *file, int num1, int num2)
-	{
-	LINE *lp;
-	int fd, lineCount, charCount;
+	newStr = cp;
+	cp = strchr(cp, delim);

-	if (bad_nums(num1, num2, "write"))
-	return FALSE;
+	if (cp)
+	*cp++ = '\0';
+	else
+	cp = (char*)"";

-	lineCount = 0;
-	charCount = 0;
+	while (cp) switch (cp++) {
+	case 'g':
+	globalFlag = TRUE;
+	break;
+	case 'p':
+	printFlag = TRUE;
+	break;
+	default:
+	bb_error_msg("unknown option for substitute");
+	return;
+	}

-	fd = creat(file, 0666);
-	if (fd < 0) {
-	bb_simple_perror_msg(file);
-	return FALSE;
+	if (*oldStr == '\0') {
+	if (searchString[0] == '\0') {
+	bb_error_msg("no previous search string");
+	return;
+	}
+	oldStr = searchString;
	}

-	printf("\"%s\", ", file);
-	fflush_all();
+	if (oldStr != searchString)
+	strcpy(searchString, oldStr);

	lp = findLine(num1);
-	if (lp == NULL) {
-	close(fd);
-	return FALSE;
-	}
+	if (lp == NULL)
+	return;

-	while (num1++ <= num2) {
-	if (full_write(fd, lp->data, lp->len) != lp->len) {
-	bb_simple_perror_msg(file);
-	close(fd);
-	return FALSE;
-	}
-	charCount += lp->len;
-	lineCount++;
-	lp = lp->next;
-	}
-
-	if (close(fd) < 0) {
-	bb_simple_perror_msg(file);
-	return FALSE;
-	}
-
-	printf("%d lines, %d chars\n", lineCount, charCount);
-	return TRUE;
-	}
-
-
-	/*
-	* Print lines in a specified range.
-	* The last line printed becomes the current line.
-	* If expandFlag is TRUE, then the line is printed specially to
-	* show magic characters.
-	*/
-	static int printLines(int num1, int num2, int expandFlag)
-	{
-	const LINE *lp;
-	const char *cp;
-	int ch, count;
-
-	if (bad_nums(num1, num2, "print"))
-	return FALSE;
-
-	lp = findLine(num1);
-	if (lp == NULL)
-	return FALSE;
+	oldLen = strlen(oldStr);
+	newLen = strlen(newStr);
+	deltaLen = newLen - oldLen;
+	offset = 0;
+	nlp = NULL;

	while (num1 <= num2) {
-	if (!expandFlag) {
-	write(STDOUT_FILENO, lp->data, lp->len);
-	setCurNum(num1++);
+	offset = findString(lp, oldStr, oldLen, offset);
+
+	if (offset < 0) {
+	if (needPrint) {
+	printLines(num1, num1, FALSE);
+	needPrint = FALSE;
+	}
+	offset = 0;
	lp = lp->next;
+	num1++;
	continue;
	}

+	needPrint = printFlag;
+	didSub = TRUE;
+	dirty = TRUE;
+
	/*
-	* Show control characters and characters with the
-	* high bit set specially.
+	* If the replacement string is the same size or shorter
+	* than the old string, then the substitution is easy.
	*/
-	cp = lp->data;
-	count = lp->len;
-
-	if ((count > 0) && (cp[count - 1] == '\n'))
-	count--;
+	if (deltaLen <= 0) {
+	memcpy(&lp->data[offset], newStr, newLen);
+	if (deltaLen) {
+	memcpy(&lp->data[offset + newLen],
+	&lp->data[offset + oldLen],
+	lp->len - offset - oldLen);

-	while (count-- > 0) {
-	ch = (unsigned char) *cp++;
-	fputc_printable(ch \| PRINTABLE_META, stdout);
+	lp->len += deltaLen;
+	}
+	offset += newLen;
+	if (globalFlag)
+	continue;
+	if (needPrint) {
+	printLines(num1, num1, FALSE);
+	needPrint = FALSE;
+	}
+	lp = lp->next;
+	num1++;
+	continue;
	}

-	fputs("$\n", stdout);
+	/*
+	* The new string is larger, so allocate a new line
+	* structure and use that. Link it in place of
+	* the old line structure.
+	*/
+	nlp = xmalloc(sizeof(LINE) + lp->len + deltaLen);

-	setCurNum(num1++);
-	lp = lp->next;
-	}
+	nlp->len = lp->len + deltaLen;

-	return TRUE;
-	}
+	memcpy(nlp->data, lp->data, offset);
+	memcpy(&nlp->data[offset], newStr, newLen);
+	memcpy(&nlp->data[offset + newLen],
+	&lp->data[offset + oldLen],
+	lp->len - offset - oldLen);

+	nlp->next = lp->next;
+	nlp->prev = lp->prev;
+	nlp->prev->next = nlp;
+	nlp->next->prev = nlp;

-	/*
-	* Insert a new line with the specified text.
-	* The line is inserted so as to become the specified line,
-	* thus pushing any existing and further lines down one.
-	* The inserted line is also set to become the current line.
-	* Returns TRUE if successful.
-	*/
-	static int insertLine(int num, const char *data, int len)
-	{
-	LINE newLp, lp;
+	if (curLine == lp)
+	curLine = nlp;

-	if ((num < 1) \|\| (num > lastNum + 1)) {
-	bb_error_msg("inserting at bad line number");
-	return FALSE;
-	}
+	free(lp);
+	lp = nlp;

-	newLp = xmalloc(sizeof(LINE) + len - 1);
+	offset += newLen;

-	memcpy(newLp->data, data, len);
-	newLp->len = len;
+	if (globalFlag)
+	continue;

-	if (num > lastNum)
-	lp = &lines;
-	else {
-	lp = findLine(num);
-	if (lp == NULL) {
-	free((char *) newLp);
-	return FALSE;
+	if (needPrint) {
+	printLines(num1, num1, FALSE);
+	needPrint = FALSE;
	}
-	}

-	newLp->next = lp;
-	newLp->prev = lp->prev;
-	lp->prev->next = newLp;
-	lp->prev = newLp;
+	lp = lp->next;
+	num1++;
+	}

-	lastNum++;
-	dirty = TRUE;
-	return setCurNum(num);
+	if (!didSub)
+	bb_error_msg("no substitutions found for \"%s\"", oldStr);
	}

-
	/*
-	* Delete lines from the given range.
+	* Read commands until we are told to stop.
	*/
-	static void deleteLines(int num1, int num2)
+	static void doCommands(void)
	{
-	LINE lp, nlp, *plp;
-	int count;
+	const char *cp;
+	char *endbuf, buf[USERSIZE];
+	int len, num1, num2;
+	smallint have1, have2;

-	if (bad_nums(num1, num2, "delete"))
-	return;
+	while (TRUE) {
+	/* Returns:
+	* -1 on read errors or EOF, or on bare Ctrl-D.
+	* 0 on ctrl-C,
+	* >0 length of input string, including terminating '\n'
+	*/
+	len = read_line_input(NULL, ": ", buf, sizeof(buf), /timeout/ -1);
+	if (len <= 0)
+	return;
+	endbuf = &buf[len - 1];
+	while ((endbuf > buf) && isblank(endbuf[-1]))
+	endbuf--;
+	*endbuf = '\0';

-	lp = findLine(num1);
-	if (lp == NULL)
-	return;
+	cp = skip_blank(buf);
+	have1 = FALSE;
+	have2 = FALSE;

-	if ((curNum >= num1) && (curNum <= num2)) {
-	if (num2 < lastNum)
-	setCurNum(num2 + 1);
-	else if (num1 > 1)
-	setCurNum(num1 - 1);
-	else
-	curNum = 0;
-	}
+	if ((curNum == 0) && (lastNum > 0)) {
+	curNum = 1;
+	curLine = lines.next;
+	}

-	count = num2 - num1 + 1;
-	if (curNum > num2)
-	curNum -= count;
-	lastNum -= count;
+	if (!getNum(&cp, &have1, &num1))
+	continue;

-	while (count-- > 0) {
-	nlp = lp->next;
-	plp = lp->prev;
-	plp->next = nlp;
-	nlp->prev = plp;
-	free(lp);
-	lp = nlp;
-	}
+	cp = skip_blank(cp);

-	dirty = TRUE;
-	}
+	if (*cp == ',') {
+	cp++;
+	if (!getNum(&cp, &have2, &num2))
+	continue;
+	if (!have1)
+	num1 = 1;
+	if (!have2)
+	num2 = lastNum;
+	have1 = TRUE;
+	have2 = TRUE;
+	}
+	if (!have1)
+	num1 = curNum;
+	if (!have2)
+	num2 = num1;

+	switch (*cp++) {
+	case 'a':
+	addLines(num1 + 1);
+	break;

-	/*
-	* Search for a line which contains the specified string.
-	* If the string is "", then the previously searched for string
-	* is used. The currently searched for string is saved for future use.
-	* Returns the line number which matches, or 0 if there was no match
-	* with an error printed.
-	*/
-	static NOINLINE int searchLines(const char *str, int num1, int num2)
-	{
-	const LINE *lp;
-	int len;
+	case 'c':
+	deleteLines(num1, num2);
+	addLines(num1);
+	break;

-	if (bad_nums(num1, num2, "search"))
-	return 0;
+	case 'd':
+	deleteLines(num1, num2);
+	break;

-	if (*str == '\0') {
-	if (searchString[0] == '\0') {
-	bb_error_msg("no previous search string");
-	return 0;
-	}
-	str = searchString;
-	}
+	case 'f':
+	if (cp && !isblank(cp)) {
+	bb_error_msg("bad file command");
+	break;
+	}
+	cp = skip_blank(cp);
+	if (*cp == '\0') {
+	if (fileName)
+	printf("\"%s\"\n", fileName);
+	else
+	puts("No file name");
+	break;
+	}
+	free(fileName);
+	fileName = xstrdup(cp);
+	break;

-	if (str != searchString)
-	strcpy(searchString, str);
+	case 'i':
+	addLines(num1);
+	break;

-	len = strlen(str);
+	case 'k':
+	cp = skip_blank(cp);
+	if ((cp < 'a') \|\| (cp > 'z') \|\| cp[1]) {
+	bb_error_msg("bad mark name");
+	break;
+	}
+	marks[*cp - 'a'] = num2;
+	break;

-	lp = findLine(num1);
-	if (lp == NULL)
-	return 0;
+	case 'l':
+	printLines(num1, num2, TRUE);
+	break;

-	while (num1 <= num2) {
-	if (findString(lp, str, len, 0) >= 0)
-	return num1;
-	num1++;
-	lp = lp->next;
-	}
+	case 'p':
+	printLines(num1, num2, FALSE);
+	break;

-	bb_error_msg("can't find string \"%s\"", str);
-	return 0;
-	}
+	case 'q':
+	cp = skip_blank(cp);
+	if (have1 \|\| *cp) {
+	bb_error_msg("bad quit command");
+	break;
+	}
+	if (!dirty)
+	return;
+	len = read_line_input(NULL, "Really quit? ", buf, 16, /timeout/ -1);
+	/* read error/EOF - no way to continue */
+	if (len < 0)
+	return;
+	cp = skip_blank(buf);
+	if ((cp \| 0x20) == 'y') / Y or y */
+	return;
+	break;

+	case 'r':
+	if (cp && !isblank(cp)) {
+	bb_error_msg("bad read command");
+	break;
+	}
+	cp = skip_blank(cp);
+	if (*cp == '\0') {
+	bb_error_msg("no file name");
+	break;
+	}
+	if (!have1)
+	num1 = lastNum;
+	if (readLines(cp, num1 + 1))
+	break;
+	if (fileName == NULL)
+	fileName = xstrdup(cp);
+	break;

-	/*
-	* Return a pointer to the specified line number.
-	*/
-	static LINE *findLine(int num)
-	{
-	LINE *lp;
-	int lnum;
+	case 's':
+	subCommand(cp, num1, num2);
+	break;

-	if ((num < 1) \|\| (num > lastNum)) {
-	bb_error_msg("line number %d does not exist", num);
-	return NULL;
-	}
+	case 'w':
+	if (cp && !isblank(cp)) {
+	bb_error_msg("bad write command");
+	break;
+	}
+	cp = skip_blank(cp);
+	if (!have1) {
+	num1 = 1;
+	num2 = lastNum;
+	}
+	if (*cp == '\0')
+	cp = fileName;
+	if (cp == NULL) {
+	bb_error_msg("no file name specified");
+	break;
+	}
+	writeLines(cp, num1, num2);
+	break;

-	if (curNum <= 0) {
-	curNum = 1;
-	curLine = lines.next;
-	}
+	case 'z':
+	switch (*cp) {
+	case '-':
+	printLines(curNum - 21, curNum, FALSE);
+	break;
+	case '.':
+	printLines(curNum - 11, curNum + 10, FALSE);
+	break;
+	default:
+	printLines(curNum, curNum + 21, FALSE);
+	break;
+	}
+	break;

-	if (num == curNum)
-	return curLine;
+	case '.':
+	if (have1) {
+	bb_error_msg("no arguments allowed");
+	break;
+	}
+	printLines(curNum, curNum, FALSE);
+	break;

-	lp = curLine;
-	lnum = curNum;
-	if (num < (curNum / 2)) {
-	lp = lines.next;
-	lnum = 1;
-	} else if (num > ((curNum + lastNum) / 2)) {
-	lp = lines.prev;
-	lnum = lastNum;
-	}
+	case '-':
+	if (setCurNum(curNum - 1))
+	printLines(curNum, curNum, FALSE);
+	break;

-	while (lnum < num) {
-	lp = lp->next;
-	lnum++;
-	}
+	case '=':
+	printf("%d\n", num1);
+	break;
+	case '\0':
+	if (have1) {
+	printLines(num2, num2, FALSE);
+	break;
+	}
+	if (setCurNum(curNum + 1))
+	printLines(curNum, curNum, FALSE);
+	break;

-	while (lnum > num) {
-	lp = lp->prev;
-	lnum--;
+	default:
+	bb_error_msg("unimplemented command");
+	break;
+	}
	}
-	return lp;
	}

-
-	/*
-	* Set the current line number.
-	* Returns TRUE if successful.
-	*/
-	static int setCurNum(int num)
+	int ed_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+	int ed_main(int argc UNUSED_PARAM, char **argv)
	{
-	LINE *lp;
+	INIT_G();

-	lp = findLine(num);
-	if (lp == NULL)
-	return FALSE;
-	curNum = num;
-	curLine = lp;
-	return TRUE;
+	bufSize = INITBUF_SIZE;
+	bufBase = xmalloc(bufSize);
+	bufPtr = bufBase;
+	lines.next = &lines;
+	lines.prev = &lines;
+
+	if (argv[1]) {
+	fileName = xstrdup(argv[1]);
+	if (!readLines(fileName, 1)) {
+	return EXIT_SUCCESS;
+	}
+	if (lastNum)
+	setCurNum(1);
+	dirty = FALSE;
+	}
+
+	doCommands();
+	return EXIT_SUCCESS;
	}