Another VAXC wildcard routine, with redirection
Richard Stanton
LC.YRS at forsythe.stanford.edu
Sat Feb 17 09:55:02 AEST 1990
Here is another wildcard routine for VAX C, which also does
redirection. Thanks to John Campbelll for the code, but please do
not send any questions to him. It is provided on a purely "as is"
basis.
----cut here for redexp.vms---
/*
This is easy to use, just put #include "redexp.vms" after your
#include <stdio.h>.
This 'C' module may be included prior to the ``main'' programs on VMS in
order to allow 'C' arguments to contain redirection symbols (<,>,>>) and
VMS wild cards (*,% ...], [-). By including this module, two programs
redirect() and expand() are run prior to turning control over to
your main() entry point.
redirect-- Gregg Townsend circa 1983,
expand-- John Campbell circa 1987
This code is public domain, others may use it freely. Credit, however, to
Gregg Townsend (who wrote ``redirect()'') and John Campbell (who followed
with ``expand()'') would be appreciated. If someone writes the next
logical successor ``pipe()'', please email a copy to
...!arizona!naucse!jdc (John Campbell) :-).
*/
#include <rms> /* No easy way to tell if this has already been included. */
#ifndef ERANGE /* Include only if missing. */
/* #include <stdlib> causes lots of warnings. */
#endif
#include <stdio.h> /* Stdio.h won't include itself twice. */
/* Expansion of wild cards is done using RMS. */
typedef struct NAMBLK { struct NAM nam; /* VMS nam block structure */
char es[NAM$C_MAXRSS], /* Extended string */
rs[NAM$C_MAXRSS]; /* Resultant string */
};
#define ErrorExit 1
/* Allow the user to override _N_FARGS or _E_FLAG if they wish. */
#ifndef _N_FARGS
#define _N_FARGS 0
#endif
#ifndef _E_FLAG
#define _E_FLAG 0
#endif
/*
Since the following will possibly be included in a single module, try
hard to avoid name conflicts. (Just being static doesn't cut it if
compiled in the same module.)
*/
#define redirect _r_edirect
#define filearg _f_ilearg
#define expand _e_xpand
#define wild_found _w_ild_found
#define wild_expand _w_ild_expand
main(argc, argv, envp)
int argc;
char *argv[], *envp[];
{
char **expand();
redirect (&argc, argv, _N_FARGS);
argv = expand (&argc, argv, _E_FLAG);
/* Make the user's main entry point this routine's entry point. */
#define main _user_main
_user_main (argc, argv, envp);
}
/*
* redirect(&argc,argv,nfargs) - redirect standard I/O
* int *argc number of command arguments (from call to main)
* char *argv[] command argument list (from call to main)
* int nfargs number of filename arguments to process
*
* argc and argv will be adjusted by redirect.
*
* redirect processes a program's command argument list and handles redirection
* of stdin, and stdout. Any arguments which redirect I/O are removed from the
* argument list, and argc is adjusted accordingly. redirect would typically be
* called as the first statement in the main program.
*
* Files are redirected based on syntax or position of command arguments.
* Arguments of the following forms always redirect a file:
*
* <file redirects standard input to read the given file
* >file redirects standard output to write to the given file
* >>file redirects standard output to append to the given file
*
* It is often useful to allow alternate input and output files as the
* first two command arguments without requiring the <file and >file
* syntax. If the nfargs argument to redirect is 2 or more then the
* first two command arguments, if supplied, will be interpreted in this
* manner: the first argument replaces stdin and the second stdout.
* A filename of "-" may be specified to occupy a position without
* performing any redirection.
*
* If nfargs is 1, only the first argument will be considered and will
* replace standard input if given. Any arguments processed by setting
* nfargs > 0 will be removed from the argument list, and again argc will
* be adjusted. Positional redirection follows syntax-specified
* redirection and therefore overrides it.
*
*/
redirect(argc,argv,nfargs)
int *argc, nfargs;
char *argv[];
{
int i;
i = 1;
while (i < *argc) { /* for every command argument... */
switch (argv[i][0]) { /* check first character */
case '<': /* <file redirects stdin */
filearg(argc,argv,i,1,stdin,"r");
break;
case '>': /* >file or >>file redirects stdout */
if (argv[i][1] == '>')
filearg(argc,argv,i,2,stdout,"a");
else
filearg(argc,argv,i,1,stdout,"w");
break;
default: /* not recognized, go on to next arg */
i++;
}
}
if (nfargs >= 1 && *argc > 1) /* if positional redirection & 1 arg */
filearg(argc,argv,1,0,stdin,"r"); /* then redirect stdin */
if (nfargs >= 2 && *argc > 1) /* likewise for 2nd arg if wanted */
filearg(argc,argv,1,0,stdout,"w");/* redirect stdout */
}
/* filearg(&argc,argv,n,i,fp,mode) - redirect and remove file argument
* int *argc number of command arguments (from call to main)
* char *argv[] command argument list (from call to main)
* int n argv entry to use as file name and then delete
* int i first character of file name to use (skip '<' etc.)
* FILE *fp file pointer for file to reopen (typically stdin etc.)
* char mode[] file access mode (see freopen spec)
*/
filearg(argc,argv,n,i,fp,mode)
int *argc, n, i;
char *argv[], mode[];
FILE *fp;
{
if (strcmp(argv[n]+i,"-")) /* alter file if arg not "-" */
fp = freopen(argv[n]+i,mode,fp);
if (fp == NULL) { /* abort on error */
fprintf(stderr,"%%can't open %s",argv[n]+i);
exit(ErrorExit);
}
for ( ; n < *argc; n++) /* move down following arguments */
argv[n] = argv[n+1];
*argc = *argc - 1; /* decrement argument count */
}
/* EXPAND code. */
/* Global prototype. */
char **expand (int *argc, const char *argv[], const int flag);
/*-
``expand()'' is a routine to expand wild-cards to file specifications.
This routine is often used in conjunction with ``redirect()'' to provide
both wild card expansion and standard file redirection prior to doing
any real work in a 'C' program.
Normal usage is to include the following line prior to using argc or
argv in main():
argv = expand (&argc, argv, 0);
``argc'' will be adjusted by ``expand()'', the return value from expand
will replace ``argv''.
``expand()'' processes a program's command argument list and expands any
wild cards into zero or more argv entries. Only arguments that posses VMS
wild-cards are expanded. Wild cards searched for are ``*'', ``%'',
``...]'', and ``[-''. If the wild-card is found inside a single or double
quote ("*" or '%') then they are not counted as wild-cards. Be aware that
the expansion of a VMS wild card will match all VMS files, including
directory files (".DIR;1").
NOTE: The use of quotes in VMS requires thinking about how the CLI expands
things before handing the argument line over to your program. Do not
expect "*" to avoid expansion, use """*""" instead. Likewise, expression
substitution precludes the use of (') to quote wild cards:
$ A := HELLO
$ ECHO 'a' ! 'C' program that calls ``expand()''
hello
The easiest way to escape a wild-card may be "'*'". The point is that
``expand()'' will only recognize quotes passed into main().
``expand()'' references the VMS runtime routines, you will need to
link with the 'C' RTL whenever expand is used.
Parameters:
argc: Pointer to the number of command arguments (from main),
the contents of this parameter are modified.
argv: Pointer to the initial command argument list (from main),
the contents are copied into a new array which is returned
from this routine.
flag: Flag indicating how to expand wild-cards:
0 - Complete file name expansion
1 - only file name (no directory or version).
2 - directory info and file name (no version).
3 - file name and version info (no directory).
-*/
/* Local prototypes. */
int wild_found (char *string);
char **wild_expand (const char *string, char **argv, int *argc,
int extra, int flag);
/*
General note: removing the prototyping and const keywords should
allow this code to compile with VMS 'C' compilers prior to version
2.3-024.
*/
char **expand (int *argc, char *argv[], int flag)
/*
Routine to expand all the arguments from main(argc,argv). The
return value is a pointer to a new (expanded) argv array.
Parameters:
argc: Pointer to the number of command arguments (from main),
the contents of this parameter are modified.
argv: Pointer to the initial command argument list (from main),
the contents are copied into a new array which is returned
from this routine.
flag: Flag indicating how to expand wild-card:
0 - Complete file name expansion
1 - only file name (no directory or version).
2 - directory info and file name (no version).
3 - file name and version info (no directory).
*/
{
int i, nargc;
char **nargv, **wild_expand();
char *start, *end;
/* Get an initial amount of memory for the master nargv array. */
if ((nargv = (char **)malloc ((*argc+1) * sizeof (char *))) == NULL) {
fprintf (stderr, "Not enough memory to expand argument list\n");
exit (ErrorExit);
}
/*
Fix the command string so that it only has the name and not the path of
the function (more in line with what unix reports with argv[0]
*/
start = argv[0];
end = argv[0] + strlen (argv[0]);
while (start < end) {
/* Scan from the back for the first '.' and replace it with a '\0' */
if (*end == '.') *end = '\0';
/* And trim off path if it is found. */
if (*end == ']') {
end++;
break;
}
--end;
}
nargv[0] = end;
/* Copy each argument, expanding those that have wild characters. */
for (nargc = i = 1; i < *argc; i++) {
if (wild_found(argv[i]))
nargv = wild_expand(argv[i], nargv, &nargc, *argc-i, flag);
else
nargv[nargc++] = argv[i];
}
*argc = nargc;
nargv[nargc] = NULL; /* realloc always 0 fills, but... */
return nargv;
}
static int wild_found (char *string)
/*
Routine to search the given string for a VMS wild-card pattern.
Returns 1 if "*", "%", "[-", or "...]" is found. (This may not
be all VMS wild-cards but it is enough for now--anyone that wants
to recognize others can change this code.)
Parameter:
string: '\0' terminated character array.
*/
{
int state = 0;
/*
State of 0 is "rest" state. State 1 on our way to [-, states 2-4
on our way to ...], negative states indicate the two quotes (' -10,
" -1).
*/
for ( ;*string; string++) {
switch (*string) {
case '*':
case '%':
if (state >= 0)
return 1; /* Unquoted % or * found. */
break;
case '[':
if (state >= 0)
state = 1;
break;
case ']':
if (state == 4)
return 1; /* Unquoted ...] found. */
else if (state >= 0)
state = 0;
break;
case '-':
if (state == 1)
return 1; /* Unquoted [- found. */
else if (state >= 0)
state = 0;
break;
case '.':
if (state == 1 || state == 0)
state = 2; /* First '.' */
else if (state > 1 && state < 5)
state++; /* ... == states 2, 3, 4 */
else if (state >= 0)
state = 0;
break;
case '\'':
if (state <= -10)
state += 10; /* One ', possibly one " also */
else if (state < 0)
state -= 10; /* 0 ', possibly one " */
else
state = -10; /* No ' or " prior to this ' */
break;
case '"':
if (state == -11)
state = -10; /* Both " and ' prior to this. */
else if (state == -10)
state = -11; /* A ' prior to this. */
else if (state == -1)
state = 0; /* A " prior to this. */
else
state = -1; /* No ' or " prior to this " */
break;
}
}
return 0;
}
static char **wild_expand (const char *wild, char **argv,
int *argc, int extra, int flag)
/*
Routine to expand wild into new arguments appended to the end
of argv[*argc]. This routine must realloc in order to make room
for the individual arguments and malloc for enough space for each
of the arguments. The return value is a new **argv.
Parameters:
wild: '\0' terminated string that needs to be expanded.
argv: initial starting address of the argv array.
argc: pointer to an integer that tells the current end of the
argument list.
extra: The number of extra pointers that the returned argv
must have available for future assignments.
flag: Flag indicating how to expand wild-card:
0 - Complete file name expansion
1 - only file name (no directory or version).
2 - directory info and file name (no version)
3 - file name and version info (no directory).
*/
{
int more_to_go = 1, err, length, status, len_wild;
char *namptr, *strncpy();
struct FAB fab_blk;
struct NAMBLK nam_blk;
len_wild = strlen(wild);
/* Initialize all the fab and nam fields needed for parse and search */
fab_blk = cc$rms_fab; /* Initialize FAB structure */
nam_blk.nam = cc$rms_nam; /* Initialize NAM structure */
fab_blk.fab$l_dna = ".*"; /* Default file specif. */
fab_blk.fab$b_dns = 2; /* Length of default spec. */
fab_blk.fab$l_nam = &nam_blk.nam; /* Set address of NAM in FAB*/
nam_blk.nam.nam$b_ess = NAM$C_MAXRSS; /* Set extended string size*/
nam_blk.nam.nam$l_esa = &nam_blk.es; /* and address */
nam_blk.nam.nam$b_rss = NAM$C_MAXRSS; /* Set resultant string size*/
nam_blk.nam.nam$l_rsa = &nam_blk.rs; /* and address */
nam_blk.nam.nam$l_rlf = NULL; /* No related file address */
fab_blk.fab$l_fna = wild; /* Address of file name string */
fab_blk.fab$b_fns = len_wild; /* Length of file name string */
/* Prepare to enter the search loop, parse fab. */
err = SYS$PARSE (&fab_blk);
/* Catch the directory not found error and return no files found. */
if (err != RMS$_NORMAL)
exit(err);
while (more_to_go) {
err = SYS$SEARCH (&fab_blk);
if (err == RMS$_NMF || err == RMS$_FNF)
more_to_go = 0; /* Done, no more files found */
else if (err != RMS$_NORMAL)
exit (err);
else {
/* Count that we now have this many arguments. */
(*argc)++;
/* Make sure there is room for a new pointer. */
if ((argv = realloc (argv, (*argc + extra)*sizeof(char *))) == NULL) {
fprintf (stderr, "Not enough memory to expand argument list\n");
exit(ErrorExit);
}
/* Move the right name into the list. */
switch (flag) {
case 0: /* Complete file name */
length = nam_blk.nam.nam$b_rsl;
namptr = &nam_blk.rs;
break;
case 1: /* File name only (no directory or version). */
length = nam_blk.nam.nam$b_name + nam_blk.nam.nam$b_type;
namptr = nam_blk.nam.nam$l_name;
break;
case 2: /* directory and file name (no version) */
length = nam_blk.nam.nam$b_rsl - nam_blk.nam.nam$b_ver;
namptr = &nam_blk.rs;
break;
case 3: /* File name and version (no directory). */
length = nam_blk.nam.nam$b_name +
nam_blk.nam.nam$b_type +
nam_blk.nam.nam$b_ver;
namptr = nam_blk.nam.nam$l_name;
break;
default:
fprintf (stderr, "illegal flag used in VMS expand call\n");
exit (ErrorExit);
}
/* Copy the requested string into the argument array. */
if ((argv[*argc-1] = malloc (length+1)) == NULL) {
fprintf (stderr, "Not enough memory to expand argument list\n");
exit (ErrorExit);
}
(void )strncpy (argv[*argc-1], namptr, length);
argv[*argc-1][length] = '\0';
}
}
return (argv);
}
/* Remove all the defines that might affect the user's code. */
#undef redirect
#undef filearg
#undef expand
#undef wild_found
#undef wild_expand
#ifdef __TST_ECHO /* Example code using expand(). */
# ifndef __FILE
#include stdio
#endif
main(argc, argv)
int argc;
char *argv[];
/*
This main program allows you to run experiments with ``expand()''.
Try $ echo *.*, $ echo -f1 [-...]*.*, $ echo -f[0-3] *.*.
Questions about using "%", "\", etc. may be answered by testing
with this version of echo.
To use this, of course, you need to link directly with expand--
avoiding the substitution of main with _user_main above.
*/
{
int i, flag=0;
char **expand();
for(i=1; i<argc; i++)
printf("%s %c", argv[i], (i<argc-1) ? ' ':'\n');
if (argc > 1 && argv[1][0] == '-' && argv[1][1] == 'f')
flag = atoi (&argv[1][2]);
argv = expand (&argc, argv, flag);
printf ("\n\n");
for(i=1; i<argc; i++)
printf("%s %c", argv[i], flag%2 == 0 ? '\n' : i%4 == 0 ? '\n':'\t');
}
#endif /* __TST_ECHO */
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