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-rw-r--r--bin/ksh/history.c981
1 files changed, 981 insertions, 0 deletions
diff --git a/bin/ksh/history.c b/bin/ksh/history.c
new file mode 100644
index 0000000..78f9fb7
--- /dev/null
+++ b/bin/ksh/history.c
@@ -0,0 +1,981 @@
+/* $OpenBSD: history.c,v 1.56 2015/12/30 09:07:00 tedu Exp $ */
+
+/*
+ * command history
+ */
+
+/*
+ * This file contains
+ * a) the original in-memory history mechanism
+ * b) a more complicated mechanism done by pc@hillside.co.uk
+ * that more closely follows the real ksh way of doing
+ * things. You need to have the mmap system call for this
+ * to work on your system
+ */
+
+#include <sys/stat.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "sh.h"
+
+#ifdef HISTORY
+# include <sys/mman.h>
+
+/*
+ * variables for handling the data file
+ */
+static int histfd;
+static int hsize;
+
+static int hist_count_lines(unsigned char *, int);
+static int hist_shrink(unsigned char *, int);
+static unsigned char *hist_skip_back(unsigned char *,int *,int);
+static void histload(Source *, unsigned char *, int);
+static void histinsert(Source *, int, unsigned char *);
+static void writehistfile(int, char *);
+static int sprinkle(int);
+
+static int hist_execute(char *);
+static int hist_replace(char **, const char *, const char *, int);
+static char **hist_get(const char *, int, int);
+static char **hist_get_oldest(void);
+static void histbackup(void);
+
+static char **current; /* current position in history[] */
+static char *hname; /* current name of history file */
+static int hstarted; /* set after hist_init() called */
+static Source *hist_source;
+
+
+int
+c_fc(char **wp)
+{
+ struct shf *shf;
+ struct temp *tf = NULL;
+ char *p, *editor = NULL;
+ int gflag = 0, lflag = 0, nflag = 0, sflag = 0, rflag = 0;
+ int optc;
+ char *first = NULL, *last = NULL;
+ char **hfirst, **hlast, **hp;
+
+ if (!Flag(FTALKING_I)) {
+ bi_errorf("history functions not available");
+ return 1;
+ }
+
+ while ((optc = ksh_getopt(wp, &builtin_opt,
+ "e:glnrs0,1,2,3,4,5,6,7,8,9,")) != -1)
+ switch (optc) {
+ case 'e':
+ p = builtin_opt.optarg;
+ if (strcmp(p, "-") == 0)
+ sflag++;
+ else {
+ size_t len = strlen(p) + 4;
+ editor = str_nsave(p, len, ATEMP);
+ strlcat(editor, " $_", len);
+ }
+ break;
+ case 'g': /* non-at&t ksh */
+ gflag++;
+ break;
+ case 'l':
+ lflag++;
+ break;
+ case 'n':
+ nflag++;
+ break;
+ case 'r':
+ rflag++;
+ break;
+ case 's': /* posix version of -e - */
+ sflag++;
+ break;
+ /* kludge city - accept -num as -- -num (kind of) */
+ case '0': case '1': case '2': case '3': case '4':
+ case '5': case '6': case '7': case '8': case '9':
+ p = shf_smprintf("-%c%s",
+ optc, builtin_opt.optarg);
+ if (!first)
+ first = p;
+ else if (!last)
+ last = p;
+ else {
+ bi_errorf("too many arguments");
+ return 1;
+ }
+ break;
+ case '?':
+ return 1;
+ }
+ wp += builtin_opt.optind;
+
+ /* Substitute and execute command */
+ if (sflag) {
+ char *pat = NULL, *rep = NULL;
+
+ if (editor || lflag || nflag || rflag) {
+ bi_errorf("can't use -e, -l, -n, -r with -s (-e -)");
+ return 1;
+ }
+
+ /* Check for pattern replacement argument */
+ if (*wp && **wp && (p = strchr(*wp + 1, '='))) {
+ pat = str_save(*wp, ATEMP);
+ p = pat + (p - *wp);
+ *p++ = '\0';
+ rep = p;
+ wp++;
+ }
+ /* Check for search prefix */
+ if (!first && (first = *wp))
+ wp++;
+ if (last || *wp) {
+ bi_errorf("too many arguments");
+ return 1;
+ }
+
+ hp = first ? hist_get(first, false, false) :
+ hist_get_newest(false);
+ if (!hp)
+ return 1;
+ return hist_replace(hp, pat, rep, gflag);
+ }
+
+ if (editor && (lflag || nflag)) {
+ bi_errorf("can't use -l, -n with -e");
+ return 1;
+ }
+
+ if (!first && (first = *wp))
+ wp++;
+ if (!last && (last = *wp))
+ wp++;
+ if (*wp) {
+ bi_errorf("too many arguments");
+ return 1;
+ }
+ if (!first) {
+ hfirst = lflag ? hist_get("-16", true, true) :
+ hist_get_newest(false);
+ if (!hfirst)
+ return 1;
+ /* can't fail if hfirst didn't fail */
+ hlast = hist_get_newest(false);
+ } else {
+ /* POSIX says not an error if first/last out of bounds
+ * when range is specified; at&t ksh and pdksh allow out of
+ * bounds for -l as well.
+ */
+ hfirst = hist_get(first, (lflag || last) ? true : false,
+ lflag ? true : false);
+ if (!hfirst)
+ return 1;
+ hlast = last ? hist_get(last, true, lflag ? true : false) :
+ (lflag ? hist_get_newest(false) : hfirst);
+ if (!hlast)
+ return 1;
+ }
+ if (hfirst > hlast) {
+ char **temp;
+
+ temp = hfirst; hfirst = hlast; hlast = temp;
+ rflag = !rflag; /* POSIX */
+ }
+
+ /* List history */
+ if (lflag) {
+ char *s, *t;
+ const char *nfmt = nflag ? "\t" : "%d\t";
+
+ for (hp = rflag ? hlast : hfirst;
+ hp >= hfirst && hp <= hlast; hp += rflag ? -1 : 1) {
+ shf_fprintf(shl_stdout, nfmt,
+ hist_source->line - (int) (histptr - hp));
+ /* print multi-line commands correctly */
+ for (s = *hp; (t = strchr(s, '\n')); s = t)
+ shf_fprintf(shl_stdout, "%.*s\t", ++t - s, s);
+ shf_fprintf(shl_stdout, "%s\n", s);
+ }
+ shf_flush(shl_stdout);
+ return 0;
+ }
+
+ /* Run editor on selected lines, then run resulting commands */
+
+ tf = maketemp(ATEMP, TT_HIST_EDIT, &genv->temps);
+ if (!(shf = tf->shf)) {
+ bi_errorf("cannot create temp file %s - %s",
+ tf->name, strerror(errno));
+ return 1;
+ }
+ for (hp = rflag ? hlast : hfirst;
+ hp >= hfirst && hp <= hlast; hp += rflag ? -1 : 1)
+ shf_fprintf(shf, "%s\n", *hp);
+ if (shf_close(shf) == EOF) {
+ bi_errorf("error writing temporary file - %s", strerror(errno));
+ return 1;
+ }
+
+ /* Ignore setstr errors here (arbitrary) */
+ setstr(local("_", false), tf->name, KSH_RETURN_ERROR);
+
+ /* XXX: source should not get trashed by this.. */
+ {
+ Source *sold = source;
+ int ret;
+
+ ret = command(editor ? editor : "${FCEDIT:-/bin/ed} $_", 0);
+ source = sold;
+ if (ret)
+ return ret;
+ }
+
+ {
+ struct stat statb;
+ XString xs;
+ char *xp;
+ int n;
+
+ if (!(shf = shf_open(tf->name, O_RDONLY, 0, 0))) {
+ bi_errorf("cannot open temp file %s", tf->name);
+ return 1;
+ }
+
+ n = fstat(shf->fd, &statb) < 0 ? 128 :
+ statb.st_size + 1;
+ Xinit(xs, xp, n, hist_source->areap);
+ while ((n = shf_read(xp, Xnleft(xs, xp), shf)) > 0) {
+ xp += n;
+ if (Xnleft(xs, xp) <= 0)
+ XcheckN(xs, xp, Xlength(xs, xp));
+ }
+ if (n < 0) {
+ bi_errorf("error reading temp file %s - %s",
+ tf->name, strerror(shf->errno_));
+ shf_close(shf);
+ return 1;
+ }
+ shf_close(shf);
+ *xp = '\0';
+ strip_nuls(Xstring(xs, xp), Xlength(xs, xp));
+ return hist_execute(Xstring(xs, xp));
+ }
+}
+
+/* Save cmd in history, execute cmd (cmd gets trashed) */
+static int
+hist_execute(char *cmd)
+{
+ Source *sold;
+ int ret;
+ char *p, *q;
+
+ histbackup();
+
+ for (p = cmd; p; p = q) {
+ if ((q = strchr(p, '\n'))) {
+ *q++ = '\0'; /* kill the newline */
+ if (!*q) /* ignore trailing newline */
+ q = NULL;
+ }
+ histsave(++(hist_source->line), p, 1);
+
+ shellf("%s\n", p); /* POSIX doesn't say this is done... */
+ if ((p = q)) /* restore \n (trailing \n not restored) */
+ q[-1] = '\n';
+ }
+
+ /* Commands are executed here instead of pushing them onto the
+ * input 'cause posix says the redirection and variable assignments
+ * in
+ * X=y fc -e - 42 2> /dev/null
+ * are to effect the repeated commands environment.
+ */
+ /* XXX: source should not get trashed by this.. */
+ sold = source;
+ ret = command(cmd, 0);
+ source = sold;
+ return ret;
+}
+
+static int
+hist_replace(char **hp, const char *pat, const char *rep, int global)
+{
+ char *line;
+
+ if (!pat)
+ line = str_save(*hp, ATEMP);
+ else {
+ char *s, *s1;
+ int pat_len = strlen(pat);
+ int rep_len = strlen(rep);
+ int len;
+ XString xs;
+ char *xp;
+ int any_subst = 0;
+
+ Xinit(xs, xp, 128, ATEMP);
+ for (s = *hp; (s1 = strstr(s, pat)) && (!any_subst || global);
+ s = s1 + pat_len) {
+ any_subst = 1;
+ len = s1 - s;
+ XcheckN(xs, xp, len + rep_len);
+ memcpy(xp, s, len); /* first part */
+ xp += len;
+ memcpy(xp, rep, rep_len); /* replacement */
+ xp += rep_len;
+ }
+ if (!any_subst) {
+ bi_errorf("substitution failed");
+ return 1;
+ }
+ len = strlen(s) + 1;
+ XcheckN(xs, xp, len);
+ memcpy(xp, s, len);
+ xp += len;
+ line = Xclose(xs, xp);
+ }
+ return hist_execute(line);
+}
+
+/*
+ * get pointer to history given pattern
+ * pattern is a number or string
+ */
+static char **
+hist_get(const char *str, int approx, int allow_cur)
+{
+ char **hp = NULL;
+ int n;
+
+ if (getn(str, &n)) {
+ hp = histptr + (n < 0 ? n : (n - hist_source->line));
+ if ((long)hp < (long)history) {
+ if (approx)
+ hp = hist_get_oldest();
+ else {
+ bi_errorf("%s: not in history", str);
+ hp = NULL;
+ }
+ } else if (hp > histptr) {
+ if (approx)
+ hp = hist_get_newest(allow_cur);
+ else {
+ bi_errorf("%s: not in history", str);
+ hp = NULL;
+ }
+ } else if (!allow_cur && hp == histptr) {
+ bi_errorf("%s: invalid range", str);
+ hp = NULL;
+ }
+ } else {
+ int anchored = *str == '?' ? (++str, 0) : 1;
+
+ /* the -1 is to avoid the current fc command */
+ n = findhist(histptr - history - 1, 0, str, anchored);
+ if (n < 0) {
+ bi_errorf("%s: not in history", str);
+ hp = NULL;
+ } else
+ hp = &history[n];
+ }
+ return hp;
+}
+
+/* Return a pointer to the newest command in the history */
+char **
+hist_get_newest(int allow_cur)
+{
+ if (histptr < history || (!allow_cur && histptr == history)) {
+ bi_errorf("no history (yet)");
+ return NULL;
+ }
+ if (allow_cur)
+ return histptr;
+ return histptr - 1;
+}
+
+/* Return a pointer to the oldest command in the history */
+static char **
+hist_get_oldest(void)
+{
+ if (histptr <= history) {
+ bi_errorf("no history (yet)");
+ return NULL;
+ }
+ return history;
+}
+
+/******************************/
+/* Back up over last histsave */
+/******************************/
+static void
+histbackup(void)
+{
+ static int last_line = -1;
+
+ if (histptr >= history && last_line != hist_source->line) {
+ hist_source->line--;
+ afree(*histptr, APERM);
+ histptr--;
+ last_line = hist_source->line;
+ }
+}
+
+/*
+ * Return the current position.
+ */
+char **
+histpos(void)
+{
+ return current;
+}
+
+int
+histnum(int n)
+{
+ int last = histptr - history;
+
+ if (n < 0 || n >= last) {
+ current = histptr;
+ return last;
+ } else {
+ current = &history[n];
+ return n;
+ }
+}
+
+/*
+ * This will become unnecessary if hist_get is modified to allow
+ * searching from positions other than the end, and in either
+ * direction.
+ */
+int
+findhist(int start, int fwd, const char *str, int anchored)
+{
+ char **hp;
+ int maxhist = histptr - history;
+ int incr = fwd ? 1 : -1;
+ int len = strlen(str);
+
+ if (start < 0 || start >= maxhist)
+ start = maxhist;
+
+ hp = &history[start];
+ for (; hp >= history && hp <= histptr; hp += incr)
+ if ((anchored && strncmp(*hp, str, len) == 0) ||
+ (!anchored && strstr(*hp, str)))
+ return hp - history;
+
+ return -1;
+}
+
+int
+findhistrel(const char *str)
+{
+ int maxhist = histptr - history;
+ int start = maxhist - 1;
+ int rec = atoi(str);
+
+ if (rec == 0)
+ return -1;
+ if (rec > 0) {
+ if (rec > maxhist)
+ return -1;
+ return rec - 1;
+ }
+ if (rec > maxhist)
+ return -1;
+ return start + rec + 1;
+}
+
+/*
+ * set history
+ * this means reallocating the dataspace
+ */
+void
+sethistsize(int n)
+{
+ if (n > 0 && n != histsize) {
+ int cursize = histptr - history;
+
+ /* save most recent history */
+ if (n < cursize) {
+ memmove(history, histptr - n, n * sizeof(char *));
+ cursize = n;
+ }
+
+ history = areallocarray(history, n, sizeof(char *), APERM);
+
+ histsize = n;
+ histptr = history + cursize;
+ }
+}
+
+/*
+ * set history file
+ * This can mean reloading/resetting/starting history file
+ * maintenance
+ */
+void
+sethistfile(const char *name)
+{
+ /* if not started then nothing to do */
+ if (hstarted == 0)
+ return;
+
+ /* if the name is the same as the name we have */
+ if (hname && strcmp(hname, name) == 0)
+ return;
+
+ /*
+ * its a new name - possibly
+ */
+ if (histfd) {
+ /* yes the file is open */
+ (void) close(histfd);
+ histfd = 0;
+ hsize = 0;
+ afree(hname, APERM);
+ hname = NULL;
+ /* let's reset the history */
+ histptr = history - 1;
+ hist_source->line = 0;
+ }
+
+ hist_init(hist_source);
+}
+
+/*
+ * initialise the history vector
+ */
+void
+init_histvec(void)
+{
+ if (history == NULL) {
+ histsize = HISTORYSIZE;
+ history = areallocarray(NULL, histsize, sizeof(char *), APERM);
+ histptr = history - 1;
+ }
+}
+
+
+/*
+ * Routines added by Peter Collinson BSDI(Europe)/Hillside Systems to
+ * a) permit HISTSIZE to control number of lines of history stored
+ * b) maintain a physical history file
+ *
+ * It turns out that there is a lot of ghastly hackery here
+ */
+
+
+/*
+ * save command in history
+ */
+void
+histsave(int lno, const char *cmd, int dowrite)
+{
+ char **hp;
+ char *c, *cp;
+
+ c = str_save(cmd, APERM);
+ if ((cp = strchr(c, '\n')) != NULL)
+ *cp = '\0';
+
+ if (histfd && dowrite)
+ writehistfile(lno, c);
+
+ hp = histptr;
+
+ if (++hp >= history + histsize) { /* remove oldest command */
+ afree(*history, APERM);
+ for (hp = history; hp < history + histsize - 1; hp++)
+ hp[0] = hp[1];
+ }
+ *hp = c;
+ histptr = hp;
+}
+
+/*
+ * Write history data to a file nominated by HISTFILE. If HISTFILE
+ * is unset then history is still recorded, but the data is not
+ * written to a file. All copies of ksh looking at the file will
+ * maintain the same history. This is ksh behaviour.
+ */
+
+/*
+ * History file format:
+ * Bytes 1, 2: HMAGIC - just to check that we are dealing with
+ the correct object
+ * Each command, in the format:
+ <command byte><command number(4 bytes)><bytes><null>
+ */
+#define HMAGIC1 0xab
+#define HMAGIC2 0xcd
+#define COMMAND 0xff
+
+void
+hist_init(Source *s)
+{
+ unsigned char *base;
+ int lines;
+ int fd;
+ struct stat sb;
+
+ if (Flag(FTALKING) == 0)
+ return;
+
+ hstarted = 1;
+
+ hist_source = s;
+
+ hname = str_val(global("HISTFILE"));
+ if (hname == NULL)
+ return;
+ hname = str_save(hname, APERM);
+
+ retry:
+ /* we have a file and are interactive */
+ if ((fd = open(hname, O_RDWR|O_CREAT|O_APPEND, 0600)) < 0)
+ return;
+ if (fstat(fd, &sb) == -1 || sb.st_uid != getuid()) {
+ close(fd);
+ return;
+ }
+
+ histfd = savefd(fd);
+ if (histfd != fd)
+ close(fd);
+
+ (void) flock(histfd, LOCK_EX);
+
+ hsize = lseek(histfd, 0L, SEEK_END);
+
+ if (hsize == 0) {
+ /* add magic */
+ if (sprinkle(histfd)) {
+ hist_finish();
+ return;
+ }
+ }
+ else if (hsize > 0) {
+ /*
+ * we have some data
+ */
+ base = mmap(0, hsize, PROT_READ,
+ MAP_FILE|MAP_PRIVATE, histfd, 0);
+ /*
+ * check on its validity
+ */
+ if (base == MAP_FAILED || *base != HMAGIC1 || base[1] != HMAGIC2) {
+ if (base != MAP_FAILED)
+ munmap((caddr_t)base, hsize);
+ hist_finish();
+ if (unlink(hname) != 0)
+ return;
+ goto retry;
+ }
+ if (hsize > 2) {
+ lines = hist_count_lines(base+2, hsize-2);
+ if (lines > histsize) {
+ /* we need to make the file smaller */
+ if (hist_shrink(base, hsize))
+ if (unlink(hname) != 0)
+ return;
+ munmap((caddr_t)base, hsize);
+ hist_finish();
+ goto retry;
+ }
+ }
+ histload(hist_source, base+2, hsize-2);
+ munmap((caddr_t)base, hsize);
+ }
+ (void) flock(histfd, LOCK_UN);
+ hsize = lseek(histfd, 0L, SEEK_END);
+}
+
+typedef enum state {
+ shdr, /* expecting a header */
+ sline, /* looking for a null byte to end the line */
+ sn1, /* bytes 1 to 4 of a line no */
+ sn2, sn3, sn4
+} State;
+
+static int
+hist_count_lines(unsigned char *base, int bytes)
+{
+ State state = shdr;
+ int lines = 0;
+
+ while (bytes--) {
+ switch (state) {
+ case shdr:
+ if (*base == COMMAND)
+ state = sn1;
+ break;
+ case sn1:
+ state = sn2; break;
+ case sn2:
+ state = sn3; break;
+ case sn3:
+ state = sn4; break;
+ case sn4:
+ state = sline; break;
+ case sline:
+ if (*base == '\0')
+ lines++, state = shdr;
+ }
+ base++;
+ }
+ return lines;
+}
+
+/*
+ * Shrink the history file to histsize lines
+ */
+static int
+hist_shrink(unsigned char *oldbase, int oldbytes)
+{
+ int fd;
+ char nfile[1024];
+ unsigned char *nbase = oldbase;
+ int nbytes = oldbytes;
+
+ nbase = hist_skip_back(nbase, &nbytes, histsize);
+ if (nbase == NULL)
+ return 1;
+ if (nbase == oldbase)
+ return 0;
+
+ /*
+ * create temp file
+ */
+ (void) shf_snprintf(nfile, sizeof(nfile), "%s.%d", hname, procpid);
+ if ((fd = open(nfile, O_CREAT | O_TRUNC | O_WRONLY, 0600)) < 0)
+ return 1;
+
+ if (sprinkle(fd)) {
+ close(fd);
+ unlink(nfile);
+ return 1;
+ }
+ if (write(fd, nbase, nbytes) != nbytes) {
+ close(fd);
+ unlink(nfile);
+ return 1;
+ }
+ close(fd);
+
+ /*
+ * rename
+ */
+ if (rename(nfile, hname) < 0)
+ return 1;
+ return 0;
+}
+
+
+/*
+ * find a pointer to the data `no' back from the end of the file
+ * return the pointer and the number of bytes left
+ */
+static unsigned char *
+hist_skip_back(unsigned char *base, int *bytes, int no)
+{
+ int lines = 0;
+ unsigned char *ep;
+
+ for (ep = base + *bytes; --ep > base; ) {
+ /* this doesn't really work: the 4 byte line number that is
+ * encoded after the COMMAND byte can itself contain the
+ * COMMAND byte....
+ */
+ for (; ep > base && *ep != COMMAND; ep--)
+ ;
+ if (ep == base)
+ break;
+ if (++lines == no) {
+ *bytes = *bytes - ((char *)ep - (char *)base);
+ return ep;
+ }
+ }
+ return NULL;
+}
+
+/*
+ * load the history structure from the stored data
+ */
+static void
+histload(Source *s, unsigned char *base, int bytes)
+{
+ State state;
+ int lno = 0;
+ unsigned char *line = NULL;
+
+ for (state = shdr; bytes-- > 0; base++) {
+ switch (state) {
+ case shdr:
+ if (*base == COMMAND)
+ state = sn1;
+ break;
+ case sn1:
+ lno = (((*base)&0xff)<<24);
+ state = sn2;
+ break;
+ case sn2:
+ lno |= (((*base)&0xff)<<16);
+ state = sn3;
+ break;
+ case sn3:
+ lno |= (((*base)&0xff)<<8);
+ state = sn4;
+ break;
+ case sn4:
+ lno |= (*base)&0xff;
+ line = base+1;
+ state = sline;
+ break;
+ case sline:
+ if (*base == '\0') {
+ /* worry about line numbers */
+ if (histptr >= history && lno-1 != s->line) {
+ /* a replacement ? */
+ histinsert(s, lno, line);
+ }
+ else {
+ s->line = lno;
+ s->cmd_offset = lno;
+ histsave(lno, (char *)line, 0);
+ }
+ state = shdr;
+ }
+ }
+ }
+}
+
+/*
+ * Insert a line into the history at a specified number
+ */
+static void
+histinsert(Source *s, int lno, unsigned char *line)
+{
+ char **hp;
+
+ if (lno >= s->line-(histptr-history) && lno <= s->line) {
+ hp = &histptr[lno-s->line];
+ afree(*hp, APERM);
+ *hp = str_save((char *)line, APERM);
+ }
+}
+
+/*
+ * write a command to the end of the history file
+ * This *MAY* seem easy but it's also necessary to check
+ * that the history file has not changed in size.
+ * If it has - then some other shell has written to it
+ * and we should read those commands to update our history
+ */
+static void
+writehistfile(int lno, char *cmd)
+{
+ int sizenow;
+ unsigned char *base;
+ unsigned char *new;
+ int bytes;
+ unsigned char hdr[5];
+
+ (void) flock(histfd, LOCK_EX);
+ sizenow = lseek(histfd, 0L, SEEK_END);
+ if (sizenow != hsize) {
+ /*
+ * Things have changed
+ */
+ if (sizenow > hsize) {
+ /* someone has added some lines */
+ bytes = sizenow - hsize;
+ base = mmap(0, sizenow,
+ PROT_READ, MAP_FILE|MAP_PRIVATE, histfd, 0);
+ if (base == MAP_FAILED)
+ goto bad;
+ new = base + hsize;
+ if (*new != COMMAND) {
+ munmap((caddr_t)base, sizenow);
+ goto bad;
+ }
+ hist_source->line--;
+ histload(hist_source, new, bytes);
+ hist_source->line++;
+ lno = hist_source->line;
+ munmap((caddr_t)base, sizenow);
+ hsize = sizenow;
+ } else {
+ /* it has shrunk */
+ /* but to what? */
+ /* we'll give up for now */
+ goto bad;
+ }
+ }
+ /*
+ * we can write our bit now
+ */
+ hdr[0] = COMMAND;
+ hdr[1] = (lno>>24)&0xff;
+ hdr[2] = (lno>>16)&0xff;
+ hdr[3] = (lno>>8)&0xff;
+ hdr[4] = lno&0xff;
+ (void) write(histfd, hdr, 5);
+ (void) write(histfd, cmd, strlen(cmd)+1);
+ hsize = lseek(histfd, 0L, SEEK_END);
+ (void) flock(histfd, LOCK_UN);
+ return;
+bad:
+ hist_finish();
+}
+
+void
+hist_finish(void)
+{
+ (void) flock(histfd, LOCK_UN);
+ (void) close(histfd);
+ histfd = 0;
+}
+
+/*
+ * add magic to the history file
+ */
+static int
+sprinkle(int fd)
+{
+ static unsigned char mag[] = { HMAGIC1, HMAGIC2 };
+
+ return(write(fd, mag, 2) != 2);
+}
+
+#else /* HISTORY */
+
+/* No history to be compiled in: dummy routines to avoid lots more ifdefs */
+void
+init_histvec(void)
+{
+}
+void
+hist_init(Source *s)
+{
+}
+void
+hist_finish(void)
+{
+}
+void
+histsave(int lno, const char *cmd, int dowrite)
+{
+ errorf("history not enabled");
+}
+#endif /* HISTORY */