diff options
Diffstat (limited to 'history')
| -rw-r--r-- | history/Makefile | 6 | ||||
| -rw-r--r-- | history/history.1 | 234 | ||||
| -rw-r--r-- | history/history.c | 333 |
3 files changed, 573 insertions, 0 deletions
diff --git a/history/Makefile b/history/Makefile new file mode 100644 index 0000000..4655947 --- /dev/null +++ b/history/Makefile @@ -0,0 +1,6 @@ +CC=gcc -g -O + +history: history.c + $(CC) -o history history.c + @echo 'Now install "history" as -, --, -p and --p in your bin directory' + @echo '(for example, by making them links to the same file)' diff --git a/history/history.1 b/history/history.1 new file mode 100644 index 0000000..18ed28f --- /dev/null +++ b/history/history.1 @@ -0,0 +1,234 @@ +.\" history.1 +.\"------- +.\" See rc.1 for man page portability notes. +.\"------- +.\" Dd distance to space vertically before a "display" +.\" These are what n/troff use for interparagraph distance +.\"------- +.if t .nr Dd .4v +.if n .nr Dd 1v +.\"------- +.\" Ds begin a display, indented .5 inches from the surrounding text. +.\" +.\" Note that uses of Ds and De may NOT be nested. +.\"------- +.de Ds +.\" .RS \\$1 +.sp \\n(Ddu +.in +0.5i +.nf +.. +.\"------- +.\" De end a display (no trailing vertical spacing) +.\"------- +.de De +.fi +.in +.\" .RE +.. +.\"------- +.\" I stole the Xf macro from the -man macros on my machine (originally +.\" "}S", I renamed it so that it won't conflict). +.\"------- +.\" Set Cf to the name of the constant width font. +.\" It will be "C" or "(CW", typically. +.\" NOTEZ BIEN the lines defining Cf must have no trailing white space: +.\"------- +.if t .ds Cf C +.if n .ds Cf R +.\"------- +.\" Rc - Alternate Roman and Courier +.\"------- +.de Rc +.Xf R \\*(Cf \& "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" +.. +.\"------- +.\" Ic - Alternate Italic and Courier +.\"------- +.de Ic +.Xf I \\*(Cf \& "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" +.. +.\"------- +.\" Bc - Alternate Bold and Courier +.\"------- +.de Bc +.Xf B \\*(Cf \& "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" +.. +.\"------- +.\" Cr - Alternate Courier and Roman +.\"------- +.de Cr +.Xf \\*(Cf R \& "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" +.. +.\"------- +.\" Ci - Alternate Courier and Italic +.\"------- +.de Ci +.Xf \\*(Cf I \& "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" +.. +.\"------- +.\" Cb - Alternate Courier and Bold +.\"------- +.de Cb +.Xf \\*(Cf B \& "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" +.. +.\"------- +.\" Xf - Alternate fonts +.\" +.\" \$1 - first font +.\" \$2 - second font +.\" \$3 - desired word with embedded font changes, built up by recursion +.\" \$4 - text for first font +.\" \$5 - \$9 - remaining args +.\" +.\" Every time we are called: +.\" +.\" If there is something in \$4 +.\" then Call ourself with the fonts switched, +.\" with a new word made of the current word (\$3) and \$4 +.\" rendered in the first font, +.\" and with the remaining args following \$4. +.\" else We are done recursing. \$3 holds the desired output +.\" word. We emit \$3, change to Roman font, and restore +.\" the point size to the default. +.\" fi +.\" +.\" Use Xi to add a little bit of space after italic text. +.\"------- +.de Xf +.ds Xi +.\"------- +.\" I used to test for the italic font both by its font position +.\" and its name. Now just test by its name. +.\" +.\" .if "\\$1"2" .if !"\\$5"" .ds Xi \^ +.\"------- +.if "\\$1"I" .if !"\\$5"" .ds Xi \^ +.\"------- +.\" This is my original code to deal with the recursion. +.\" Evidently some nroffs can't deal with it. +.\"------- +.\" .ie !"\\$4"" \{\ +.\" . Xf \\$2 \\$1 "\\$3\\f\\$1\\$4\\*(Xi" "\\$5" "\\$6" "\\$7" "\\$8" "\\$9" +.\" .\} +.\" .el \{\\$3 +.\" . ft R \" Restore the default font, since we don't know +.\" . \" what the last font change was. +.\" . ps 10 \" Restore the default point size, since it might +.\" . \" have been changed by an argument to this macro. +.\" .\} +.\"------- +.\" Here is more portable (though less pretty) code to deal with +.\" the recursion. +.\"------- +.if !"\\$4"" .Xf \\$2 \\$1 "\\$3\\f\\$1\\$4\\*(Xi" "\\$5" "\\$6" "\\$7" "\\$8" "\\$9" +.if "\\$4"" \\$3\fR\s10 +.. +.TH HISTORY 1 "30 July 1991" +.SH NAME +\-, \-\|\-, \-p, \-\|\-p \- shell history programs +.SH SYNOPSIS +.B \- +.RI [ pattern ...] +.RI [ substitution ...] +.SH DESCRIPTION +This set of programs provides a crude history mechanism for the shell +.IR rc (1). +It is based on the v8 UNIX programs +.IR = , +.IR == , +etc. +.PP +The program +.RI `` \- '' +runs the shell on the command it is requested to find. +The program +.RI `` \-\|\- '' +edits that command first. +The programs +.RI `` \-p '' +and +.RI `` \-\|\-p '' +are similar, except that they print the final command on their standard +output instead of running the shell. +.PP +The commands work by looking for a file +named by the environment variable +.Cr $history , +and by searching for previous commands in this file. +Old commands can be edited, +or simply re-executed according to the rules below: +.PP +A command is searched for by examining the lines in +.Cr $history +in reverse order. +Lines which contain a previous invocation of the history +program itself are ignored. +If one or more +.I pattern +is supplied on the command line, +then the patterns are used as a means of +limiting the search. +Patterns match any substring of a previous command, +and if more than one pattern is present then all patterns must be +matched before a command is selected. +.PP +Substitutions may also be specified on the command line. +These have the syntax: +.Ds +.Ic old : new +.De +.PP +(Note that the +.I old +pattern is used as a search-limiting pattern also.) +Substitutions happen on the first match. +.PP +Finally, a command may be edited in a crude line-mode fashion: +The line to be edited is printed out, and below it the user +supplies modifications to the command: +.TP +.B any character +Replaces the character above. +.TP +.B space or tab +Skips over the above character(s). +.TP +.B # +Deletes one character. +.TP +.B % +Replaces one character with a space. +.TP +.B ^ +Inserts the rest of the typed line just before the character. +.TP +.B $ +Deletes the rest of the line from that character on, and replaces +it with the rest of the typed line. +.TP +.B + +Appends the rest of the typed line. +.TP +.B \- +Backs up to a previous command satisfying the same matching +constraints. +.TP +.B end of file +If an end-of-file is read from the keyboard by the editor, +it aborts with exit status 1 and does not produce any output. +.SH EXAMPLES +The history programs work best when their output is reinterpreted by +the shell using an +.Cr eval +command. +This can be achieved by writing a shell function to perform the +reinterpretation: +.Ds +.Cr "fn - -- {" +.Cr " comm = \`{$0^p $*}" +.Cr " if (! ~ $#comm 0) {" +.Cr " echo $comm >[1=2]" +.Cr " eval $comm" +.Cr " }" +.Cr "}" diff --git a/history/history.c b/history/history.c new file mode 100644 index 0000000..5f2cece --- /dev/null +++ b/history/history.c @@ -0,0 +1,333 @@ +/* + 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 || *u == '`' || *u == '{' || *u == '|' || *u == '(' || *u == ')') + goto again; + } + 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; +} |