commit edf6d5059cbb06ad0cd1c5b126cd9359e4ea32e8
parent 5e91362042e4c1b7023ce18ef7e81ab144fd6928
Author: tim <tim>
Date: Wed, 4 Jun 1997 15:02:34 +0000
Initial revision
Diffstat:
| A | history.c | | | 341 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
1 file changed, 341 insertions(+), 0 deletions(-)
diff --git a/history.c b/history.c
@@ -0,0 +1,341 @@
+/*
+ history.c -- primitive history mechanism
+
+ Paul Haahr & Byron Rakitzis, July 1991.
+
+ This program mimics the att v8 = and == history programs.
+ The edit() algorithm was adapted from a similar program
+ that Boyd Roberts wrote, but otherwise all the code has
+ been written from scratch.
+
+ edit() was subsequently redone by Hugh Redelmeier in order
+ to correctly deal with tab characters in the source line.
+
+ BUGS:
+ There is an implicit assumption that commands are no
+ more than 1k characters long.
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static char *id = "@(#) history.c 8/91";
+
+#undef FALSE
+#undef TRUE
+typedef enum { FALSE, TRUE } bool;
+
+#define CHUNKSIZE 65536
+
+static struct {
+ char *old, *new;
+} *replace;
+
+static char **search, *progname, *history;
+static char me; /* typically ':' or '-' */
+static bool editit = FALSE, printit = FALSE;
+static int nreplace = 0, nsearch = 0;
+static FILE *fp;
+
+static void *ealloc(size_t n) {
+ void *p = (void *) malloc(n);
+ if (p == NULL) {
+ perror("malloc");
+ exit(1);
+ }
+ return p;
+}
+
+static void *erealloc(void *p, size_t n) {
+ p = (void *) realloc(p, n);
+ if (p == NULL) {
+ perror("realloc");
+ exit(1);
+ }
+ return p;
+}
+
+static char *newstr() {
+ return ealloc((size_t)1024);
+}
+
+static char *basename(char *s) {
+ char *t = strrchr(s, '/');
+ return (t == NULL) ? s : t + 1;
+}
+
+/* stupid O(n^2) substring matching routine */
+
+static char *isin(char *target, char *pattern) {
+ size_t plen = strlen(pattern);
+ size_t tlen = strlen(target);
+ for (; tlen >= plen; target++, --tlen)
+ if (strncmp(target, pattern, plen) == 0)
+ return target;
+ return NULL;
+}
+
+/* replace the first match in the string with "new" */
+static char *sub(char *s, char *old, char *new) {
+ char *t, *u;
+
+ t = isin(s, old);
+ u = newstr();
+
+ *t = '\0';
+ while (*old != '\0')
+ old++, t++;
+ strcpy(u, s);
+ strcat(u, new);
+ strcat(u, t);
+ return u;
+}
+
+static char *edit(char *s) {
+ char *final, *f, *end;
+ int col;
+ bool ins;
+
+start:
+ fprintf(stderr, "%s\n", s);
+ f = final = newstr();
+ end = s + strlen(s);
+ col = 0;
+ ins = FALSE;
+
+ for (;; col++) {
+ int c = getchar();
+
+ if (c == me && col == 0) {
+ int peekc = getchar();
+ if (peekc == '\n')
+ return NULL;
+ ungetc(peekc, stdin);
+ }
+ if (c == '\n') {
+ if (col == 0)
+ return s;
+
+ while (s < end) /* copy remainder of string */
+ *f++ = *s++;
+ *f = '\0';
+ s = final;
+ goto start;
+ } else if (ins || s>=end) {
+ /* col need not be accurate -- tabs need not be interpreted */
+ *f++ = c;
+ } else {
+ switch (c) {
+ case '+':
+ while (s < end)
+ *f++ = *s++;
+ *f = '\0';
+ continue;
+ case '%':
+ c = ' ';
+ /* FALLTHROUGH */
+ default:
+ *f++ = c;
+ break;
+ case EOF:
+ exit(1);
+ /* NOTREACHED */
+ case ' ':
+ if (*s == '\t') {
+ int oldcol = col;
+
+ for (;; col++) {
+ int peekc;
+
+ if ((col&07) == 07) {
+ *f++ = '\t'; /* we spaced past a tab */
+ break;
+ }
+ peekc = getchar();
+ if (peekc != ' ') {
+ ungetc(peekc, stdin);
+ if (peekc != '\n') {
+ /* we spaced partially into a tab */
+ do {
+ *f++ = ' ';
+ oldcol++;
+ } while (oldcol <= col);
+ }
+ break;
+ }
+ }
+ } else {
+ *f++ = *s;
+ }
+ break;
+ case '#':
+ break;
+ case '$':
+ end = s; /* truncate s */
+ continue; /* skip incrementing s */
+ case '^':
+ ins = TRUE;
+ continue; /* skip incrementing s */
+ case '\t':
+ for (;; col++) {
+ if ((*f++ = s<end? *s++ : '\t') == '\t') {
+ col = col | 07; /* advance to before next tabstop */
+ }
+ if ((col&07) == 07) /* stop before tabstop */
+ break;
+ }
+ continue; /* skip incrementing s */
+ }
+ if (s<end && (*s!='\t' || (col&07)==07))
+ s++;
+ }
+ }
+}
+
+static char *readhistoryfile(char **last) {
+ char *buf;
+ size_t count, size;
+ long nread;
+
+ if ((history = getenv("history")) == NULL) {
+ fprintf(stderr, "$history not set\n");
+ exit(1);
+ }
+ fp = fopen(history, "r+");
+ if (fp == NULL) {
+ perror(history);
+ exit(1);
+ }
+
+ size = 0;
+ count = 0;
+ buf = ealloc(size = CHUNKSIZE);
+ while ((nread = fread(buf + count, sizeof (char), size - count, fp)) > 0) {
+ count += nread;
+ if (size - count == 0)
+ buf = erealloc(buf, size *= 4);
+ }
+ if (nread == -1) {
+ perror(history);
+ exit(1);
+ }
+ *last = buf + count;
+ return buf;
+}
+
+static char *getcommand() {
+ char *s, *t;
+ static char *hist = NULL, *last;
+
+ if (hist == NULL) {
+ hist = readhistoryfile(&last);
+ *--last = '\0'; /* trim final newline */
+ }
+
+again: s = last;
+ if (s < hist)
+ return NULL;
+ while (*--s != '\n')
+ if (s <= hist) {
+ last = hist - 1;
+ return hist;
+ }
+ *s = '\0';
+ last = s++;
+
+ /*
+ * if the command contains the "me" character at the start of the line
+ * or after any of [`{|()@] then try again
+ */
+
+ for (t = s; *t != '\0'; t++)
+ if (*t == me) {
+ char *u = t - 1;
+ while (u >= s && (*u == ' ' || *u == '\t'))
+ --u;
+ if (u < s)
+ goto again;
+ switch (*u) {
+ case '`': case '@':
+ case '(': case ')':
+ case '{': case '|':
+ goto again;
+ default:
+ break;
+ }
+ }
+ return s;
+}
+
+int main(int argc, char **argv) {
+ int i;
+ char *s;
+
+ s = progname = basename(argv[0]);
+ me = *s++;
+ if (*s == me) {
+ s++;
+ editit = TRUE;
+ }
+ if (*s == 'p') {
+ s++;
+ printit = TRUE;
+ }
+/* Nahh...
+ if (*s != '\0') {
+ fprintf(stderr, "\"%s\": bad name for history program\n", progname);
+ exit(1);
+ }
+*/
+
+ if (argc > 1) {
+ replace = ealloc((argc - 1) * sizeof *replace);
+ search = ealloc((argc - 1) * sizeof *search);
+ }
+ for (i = 1; i < argc; i++)
+ if ((s = strchr(argv[i], ':')) == NULL)
+ search[nsearch++] = argv[i];
+ else {
+ *(char *)s = '\0'; /* do we confuse ps too much? */
+ replace[nreplace].old = argv[i];
+ replace[nreplace].new = s + 1;
+ nreplace++;
+ }
+
+next: s = getcommand();
+ if (s == NULL) {
+ fprintf(stderr, "command not matched\n");
+ return 1;
+ }
+ for (i = 0; i < nsearch; i++)
+ if (!isin(s, search[i]))
+ goto next;
+ for (i = 0; i < nreplace; i++)
+ if (!isin(s, replace[i].old))
+ goto next;
+ else
+ s = sub(s, replace[i].old, replace[i].new);
+ if (editit) {
+ s = edit(s);
+ if (s == NULL)
+ goto next;
+ }
+ fseek(fp, 0, 2); /* 2 == end of file. i.e., append command to $history */
+ fprintf(fp, "%s\n", s);
+ fclose(fp);
+ if (printit)
+ printf("%s\n", s);
+ else {
+ char *shell = getenv("SHELL");
+
+ if (!editit)
+ fprintf(stderr, "%s\n", s);
+ if (shell == NULL)
+ shell = "/bin/sh";
+ execl(shell, basename(shell), "-c", s, NULL);
+ perror(shell);
+ exit(1);
+ }
+ return 0;
+}
