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-rw-r--r--release/src/router/busybox/editors/ed.c1049
1 files changed, 1049 insertions, 0 deletions
diff --git a/release/src/router/busybox/editors/ed.c b/release/src/router/busybox/editors/ed.c
new file mode 100644
index 00000000..9084a17f
--- /dev/null
+++ b/release/src/router/busybox/editors/ed.c
@@ -0,0 +1,1049 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Copyright (c) 2002 by David I. Bell
+ * Permission is granted to use, distribute, or modify this source,
+ * provided that this copyright notice remains intact.
+ *
+ * The "ed" built-in command (much simplified)
+ */
+
+#include "libbb.h"
+
+typedef struct LINE {
+ struct LINE *next;
+ struct LINE *prev;
+ int len;
+ char data[1];
+} LINE;
+
+
+#define searchString bb_common_bufsiz1
+
+enum {
+ USERSIZE = sizeof(searchString) > 1024 ? 1024
+ : sizeof(searchString) - 1, /* max line length typed in by user */
+ INITBUF_SIZE = 1024, /* initial buffer size */
+};
+
+struct globals {
+ int curNum;
+ int lastNum;
+ int bufUsed;
+ int bufSize;
+ LINE *curLine;
+ char *bufBase;
+ char *bufPtr;
+ char *fileName;
+ LINE lines;
+ smallint dirty;
+ int marks[26];
+};
+#define G (*ptr_to_globals)
+#define curLine (G.curLine )
+#define bufBase (G.bufBase )
+#define bufPtr (G.bufPtr )
+#define fileName (G.fileName )
+#define curNum (G.curNum )
+#define lastNum (G.lastNum )
+#define bufUsed (G.bufUsed )
+#define bufSize (G.bufSize )
+#define dirty (G.dirty )
+#define lines (G.lines )
+#define marks (G.marks )
+#define INIT_G() do { \
+ 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)) {
+ bb_error_msg("bad line range for %s", for_what);
+ return 1;
+ }
+ return 0;
+}
+
+
+static char *skip_blank(const char *cp)
+{
+ while (isblank(*cp))
+ cp++;
+ return (char *)cp;
+}
+
+
+int ed_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int ed_main(int argc UNUSED_PARAM, char **argv)
+{
+ INIT_G();
+
+ 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;
+}
+
+/*
+ * Read commands until we are told to stop.
+ */
+static void doCommands(void)
+{
+ const char *cp;
+ char *endbuf, buf[USERSIZE];
+ int len, num1, num2;
+ smallint have1, have2;
+
+ 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(": ", buf, sizeof(buf), NULL);
+ if (len <= 0)
+ return;
+ endbuf = &buf[len - 1];
+ while ((endbuf > buf) && isblank(endbuf[-1]))
+ endbuf--;
+ *endbuf = '\0';
+
+ cp = skip_blank(buf);
+ have1 = FALSE;
+ have2 = FALSE;
+
+ if ((curNum == 0) && (lastNum > 0)) {
+ curNum = 1;
+ curLine = lines.next;
+ }
+
+ if (!getNum(&cp, &have1, &num1))
+ continue;
+
+ cp = skip_blank(cp);
+
+ 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;
+
+ case 'c':
+ deleteLines(num1, num2);
+ addLines(num1);
+ break;
+
+ case 'd':
+ deleteLines(num1, num2);
+ break;
+
+ 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
+ printf("No file name\n");
+ break;
+ }
+ free(fileName);
+ fileName = xstrdup(cp);
+ break;
+
+ case 'i':
+ addLines(num1);
+ break;
+
+ 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;
+
+ case 'l':
+ printLines(num1, num2, TRUE);
+ break;
+
+ case 'p':
+ printLines(num1, num2, FALSE);
+ break;
+
+ case 'q':
+ cp = skip_blank(cp);
+ if (have1 || *cp) {
+ bb_error_msg("bad quit command");
+ break;
+ }
+ if (!dirty)
+ return;
+ len = read_line_input("Really quit? ", buf, 16, NULL);
+ /* 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;
+
+ 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");
+ break;
+ }
+ writeLines(cp, num1, num2);
+ break;
+
+ 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;
+
+ case '.':
+ if (have1) {
+ bb_error_msg("no arguments allowed");
+ break;
+ }
+ printLines(curNum, curNum, FALSE);
+ break;
+
+ case '-':
+ if (setCurNum(curNum - 1))
+ printLines(curNum, curNum, FALSE);
+ break;
+
+ case '=':
+ printf("%d\n", num1);
+ break;
+ case '\0':
+ if (have1) {
+ printLines(num2, num2, FALSE);
+ break;
+ }
+ if (setCurNum(curNum + 1))
+ printLines(curNum, curNum, FALSE);
+ break;
+
+ default:
+ bb_error_msg("unimplemented command");
+ break;
+ }
+ }
+}
+
+
+/*
+ * 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 (bad_nums(num1, num2, "substitute"))
+ return;
+
+ globalFlag = FALSE;
+ printFlag = FALSE;
+ didSub = FALSE;
+ needPrint = FALSE;
+
+ /*
+ * Copy the command so we can modify it.
+ */
+ strcpy(buf, cmd);
+ cp = buf;
+
+ if (isblank(*cp) || (*cp == '\0')) {
+ bb_error_msg("bad delimiter for substitute");
+ return;
+ }
+
+ delim = *cp++;
+ oldStr = cp;
+
+ cp = strchr(cp, delim);
+ if (cp == NULL) {
+ bb_error_msg("missing 2nd delimiter for substitute");
+ return;
+ }
+
+ *cp++ = '\0';
+
+ newStr = cp;
+ cp = strchr(cp, delim);
+
+ if (cp)
+ *cp++ = '\0';
+ else
+ cp = (char*)"";
+
+ while (*cp) switch (*cp++) {
+ case 'g':
+ globalFlag = TRUE;
+ break;
+ case 'p':
+ printFlag = TRUE;
+ break;
+ default:
+ bb_error_msg("unknown option for substitute");
+ return;
+ }
+
+ if (*oldStr == '\0') {
+ if (searchString[0] == '\0') {
+ bb_error_msg("no previous search string");
+ return;
+ }
+ oldStr = searchString;
+ }
+
+ if (oldStr != searchString)
+ strcpy(searchString, oldStr);
+
+ lp = findLine(num1);
+ if (lp == NULL)
+ return;
+
+ oldLen = strlen(oldStr);
+ newLen = strlen(newStr);
+ deltaLen = newLen - oldLen;
+ offset = 0;
+ nlp = NULL;
+
+ while (num1 <= num2) {
+ 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;
+
+ /*
+ * 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);
+
+ lp->len += deltaLen;
+ }
+ offset += newLen;
+ if (globalFlag)
+ continue;
+ if (needPrint) {
+ printLines(num1, num1, FALSE);
+ needPrint = FALSE;
+ }
+ lp = lp->next;
+ num1++;
+ continue;
+ }
+
+ /*
+ * The new string is larger, so allocate a new line
+ * structure and use that. Link it in in place of
+ * the old line structure.
+ */
+ nlp = malloc(sizeof(LINE) + lp->len + deltaLen);
+ if (nlp == NULL) {
+ bb_error_msg("cannot get memory for line");
+ return;
+ }
+
+ 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;
+
+ free(lp);
+ lp = nlp;
+
+ offset += newLen;
+
+ if (globalFlag)
+ continue;
+
+ if (needPrint) {
+ printLines(num1, num1, FALSE);
+ needPrint = FALSE;
+ }
+
+ lp = lp->next;
+ num1++;
+ }
+
+ if (!didSub)
+ bb_error_msg("no substitutions found for \"%s\"", oldStr);
+}
+
+
+/*
+ * 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 int findString(const LINE *lp, const char *str, int len, int offset)
+{
+ int left;
+ const char *cp, *ncp;
+
+ cp = &lp->data[offset];
+ left = lp->len - offset;
+
+ 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--;
+ }
+
+ return -1;
+}
+
+
+/*
+ * 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];
+
+ 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("", buf, sizeof(buf), NULL);
+ if (len <= 0) {
+ /* Previously, ctrl-C was exiting to shell.
+ * Now we exit to ed prompt. Is in important? */
+ return;
+ }
+ if ((buf[0] == '.') && (buf[1] == '\n') && (buf[2] == '\0'))
+ return;
+ if (!insertLine(num++, buf, len))
+ return;
+ }
+}
+
+
+/*
+ * Parse a line number argument if it is present. This is a sum
+ * or difference of numbers, '.', '$', 'x, or a search string.
+ * Returns TRUE if successful (whether or not there was a number).
+ * Returns FALSE if there was a parsing error, with a message output.
+ * Whether there was a number is returned indirectly, as is the number.
+ * The character pointer which stopped the scan is also returned.
+ */
+static int getNum(const char **retcp, smallint *retHaveNum, int *retNum)
+{
+ const char *cp;
+ char *endStr, str[USERSIZE];
+ int value, num;
+ smallint haveNum, minus;
+
+ cp = *retcp;
+ value = 0;
+ haveNum = FALSE;
+ minus = 0;
+
+ while (TRUE) {
+ cp = skip_blank(cp);
+
+ switch (*cp) {
+ case '.':
+ haveNum = TRUE;
+ num = curNum;
+ cp++;
+ break;
+
+ case '$':
+ 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;
+
+ 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:
+ if (!isdigit(*cp)) {
+ *retcp = cp;
+ *retHaveNum = haveNum;
+ *retNum = value;
+ return TRUE;
+ }
+ num = 0;
+ while (isdigit(*cp))
+ num = num * 10 + *cp++ - '0';
+ haveNum = TRUE;
+ break;
+ }
+
+ value += (minus ? -num : num);
+
+ cp = skip_blank(cp);
+
+ switch (*cp) {
+ case '-':
+ minus = 1;
+ cp++;
+ break;
+
+ case '+':
+ minus = 0;
+ cp++;
+ break;
+
+ default:
+ *retcp = cp;
+ *retHaveNum = haveNum;
+ *retNum = value;
+ return TRUE;
+ }
+ }
+}
+
+
+/*
+ * 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;
+
+ if ((num < 1) || (num > lastNum + 1)) {
+ bb_error_msg("bad line for read");
+ return FALSE;
+ }
+
+ fd = open(file, 0);
+ if (fd < 0) {
+ perror(file);
+ return FALSE;
+ }
+
+ bufPtr = bufBase;
+ bufUsed = 0;
+ lineCount = 0;
+ charCount = 0;
+ cc = 0;
+
+ printf("\"%s\", ", file);
+ fflush(stdout);
+
+ do {
+ cp = memchr(bufPtr, '\n', bufUsed);
+
+ if (cp) {
+ len = (cp - bufPtr) + 1;
+ if (!insertLine(num, bufPtr, len)) {
+ close(fd);
+ return FALSE;
+ }
+ bufPtr += len;
+ bufUsed -= len;
+ charCount += len;
+ lineCount++;
+ num++;
+ continue;
+ }
+
+ if (bufPtr != bufBase) {
+ memcpy(bufBase, bufPtr, bufUsed);
+ bufPtr = bufBase + bufUsed;
+ }
+
+ if (bufUsed >= bufSize) {
+ len = (bufSize * 3) / 2;
+ cp = realloc(bufBase, len);
+ if (cp == NULL) {
+ bb_error_msg("no memory for buffer");
+ close(fd);
+ return FALSE;
+ }
+ bufBase = cp;
+ bufPtr = bufBase + bufUsed;
+ bufSize = len;
+ }
+
+ cc = safe_read(fd, bufPtr, bufSize - bufUsed);
+ bufUsed += cc;
+ bufPtr = bufBase;
+
+ } while (cc > 0);
+
+ if (cc < 0) {
+ perror(file);
+ close(fd);
+ return FALSE;
+ }
+
+ if (bufUsed) {
+ if (!insertLine(num, bufPtr, bufUsed)) {
+ close(fd);
+ return -1;
+ }
+ lineCount++;
+ charCount += bufUsed;
+ }
+
+ close(fd);
+
+ printf("%d lines%s, %d chars\n", lineCount,
+ (bufUsed ? " (incomplete)" : ""), charCount);
+
+ return TRUE;
+}
+
+
+/*
+ * 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;
+
+ if (bad_nums(num1, num2, "write"))
+ return FALSE;
+
+ lineCount = 0;
+ charCount = 0;
+
+ fd = creat(file, 0666);
+ if (fd < 0) {
+ perror(file);
+ return FALSE;
+ }
+
+ printf("\"%s\", ", file);
+ fflush(stdout);
+
+ lp = findLine(num1);
+ if (lp == NULL) {
+ close(fd);
+ return FALSE;
+ }
+
+ while (num1++ <= num2) {
+ if (full_write(fd, lp->data, lp->len) != lp->len) {
+ perror(file);
+ close(fd);
+ return FALSE;
+ }
+ charCount += lp->len;
+ lineCount++;
+ lp = lp->next;
+ }
+
+ if (close(fd) < 0) {
+ perror(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;
+
+ while (num1 <= num2) {
+ if (!expandFlag) {
+ write(STDOUT_FILENO, lp->data, lp->len);
+ setCurNum(num1++);
+ lp = lp->next;
+ continue;
+ }
+
+ /*
+ * Show control characters and characters with the
+ * high bit set specially.
+ */
+ cp = lp->data;
+ count = lp->len;
+
+ if ((count > 0) && (cp[count - 1] == '\n'))
+ count--;
+
+ while (count-- > 0) {
+ ch = (unsigned char) *cp++;
+ fputc_printable(ch | PRINTABLE_META, stdout);
+ }
+
+ fputs("$\n", stdout);
+
+ setCurNum(num1++);
+ lp = lp->next;
+ }
+
+ return TRUE;
+}
+
+
+/*
+ * 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 ((num < 1) || (num > lastNum + 1)) {
+ bb_error_msg("inserting at bad line number");
+ return FALSE;
+ }
+
+ newLp = malloc(sizeof(LINE) + len - 1);
+ if (newLp == NULL) {
+ bb_error_msg("failed to allocate memory for line");
+ return FALSE;
+ }
+
+ memcpy(newLp->data, data, len);
+ newLp->len = len;
+
+ if (num > lastNum)
+ lp = &lines;
+ else {
+ lp = findLine(num);
+ if (lp == NULL) {
+ free((char *) newLp);
+ return FALSE;
+ }
+ }
+
+ newLp->next = lp;
+ newLp->prev = lp->prev;
+ lp->prev->next = newLp;
+ lp->prev = newLp;
+
+ lastNum++;
+ dirty = TRUE;
+ return setCurNum(num);
+}
+
+
+/*
+ * Delete lines from the given range.
+ */
+static void deleteLines(int num1, int num2)
+{
+ LINE *lp, *nlp, *plp;
+ int count;
+
+ if (bad_nums(num1, num2, "delete"))
+ return;
+
+ lp = findLine(num1);
+ if (lp == NULL)
+ return;
+
+ if ((curNum >= num1) && (curNum <= num2)) {
+ if (num2 < lastNum)
+ setCurNum(num2 + 1);
+ else if (num1 > 1)
+ setCurNum(num1 - 1);
+ else
+ curNum = 0;
+ }
+
+ count = num2 - num1 + 1;
+ if (curNum > num2)
+ curNum -= count;
+ lastNum -= count;
+
+ while (count-- > 0) {
+ nlp = lp->next;
+ plp = lp->prev;
+ plp->next = nlp;
+ nlp->prev = plp;
+ free(lp);
+ lp = nlp;
+ }
+
+ dirty = TRUE;
+}
+
+
+/*
+ * 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 int searchLines(const char *str, int num1, int num2)
+{
+ const LINE *lp;
+ int len;
+
+ if (bad_nums(num1, num2, "search"))
+ return 0;
+
+ if (*str == '\0') {
+ if (searchString[0] == '\0') {
+ bb_error_msg("no previous search string");
+ return 0;
+ }
+ str = searchString;
+ }
+
+ if (str != searchString)
+ strcpy(searchString, str);
+
+ len = strlen(str);
+
+ lp = findLine(num1);
+ if (lp == NULL)
+ return 0;
+
+ while (num1 <= num2) {
+ if (findString(lp, str, len, 0) >= 0)
+ return num1;
+ num1++;
+ lp = lp->next;
+ }
+
+ bb_error_msg("cannot find string \"%s\"", str);
+ return 0;
+}
+
+
+/*
+ * Return a pointer to the specified line number.
+ */
+static LINE *findLine(int num)
+{
+ LINE *lp;
+ int lnum;
+
+ if ((num < 1) || (num > lastNum)) {
+ bb_error_msg("line number %d does not exist", num);
+ return NULL;
+ }
+
+ if (curNum <= 0) {
+ curNum = 1;
+ curLine = lines.next;
+ }
+
+ 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;
+}
+
+
+/*
+ * Set the current line number.
+ * Returns TRUE if successful.
+ */
+static int setCurNum(int num)
+{
+ LINE *lp;
+
+ lp = findLine(num);
+ if (lp == NULL)
+ return FALSE;
+ curNum = num;
+ curLine = lp;
+ return TRUE;
+}