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/*----------------------------------------------------------------*
| envargs - add default options from environment to command line
|----------------------------------------------------------------
| Author: Bill Davidsen, original 10/13/91, revised 23 Oct 1991.
| This program is in the public domain.
|----------------------------------------------------------------
| Minor program notes:
| 1. Yes, the indirection is a tad complex
| 2. Parenthesis were added where not needed in some cases
| to make the action of the code less obscure.
| 3. Set tabsize to four to make this pretty
|----------------------------------------------------------------
| UnZip notes 24 May 92 ("v1.4"):
| 1. #include "unzip.h" for prototypes
| 2. changed ch to type char
| 3. added an ifdef to avoid Borland warnings
|
| UnZip notes 4 Dec 93 ("v1.5"):
| 1. included Rich Wales' mksargs() routine (for MS-DOS, maybe
| OS/2? NT?)
*----------------------------------------------------------------*/
#include "unzip.h"
static int count_args __((char *));
static void mem_err __((void));
#if (defined(SCCS) && !defined(lint)) /* causes warnings: annoying */
static char *SCCSid = "@(#)envargs.c 1.3 23 Oct 1991";
#endif
void envargs(Pargc, Pargv, envstr)
int *Pargc;
char ***Pargv, *envstr;
{
char *getenv();
char *envptr; /* value returned by getenv */
char *bufptr; /* copy of env info */
int argc = 0; /* internal arg count */
char ch; /* spare temp value */
char **argv; /* internal arg vector */
char **argvect; /* copy of vector address */
/* see if anything in the environment */
envptr = getenv(envstr);
if (envptr == (char *)NULL || *envptr == 0)
return;
/* count the args so we can allocate room for them */
argc = count_args(envptr);
bufptr = (char *)malloc(1+strlen(envptr));
if (bufptr == (char *)NULL)
mem_err();
strcpy(bufptr, envptr);
/* allocate a vector large enough for all args */
argv = (char **)malloc((argc+*Pargc+1)*sizeof(char *));
if (argv == (char **)NULL)
mem_err();
argvect = argv;
/* copy the program name first, that's always true */
*(argv++) = *((*Pargv)++);
/* copy the environment args next, may be changed */
do {
*(argv++) = bufptr;
/* skip the arg and any trailing blanks */
while (((ch = *bufptr) != '\0') && ch != ' ')
++bufptr;
if (ch == ' ')
*(bufptr++) = '\0';
while (((ch = *bufptr) != '\0') && ch == ' ')
++bufptr;
} while (ch);
/* now save old argc and copy in the old args */
argc += *Pargc;
while (--(*Pargc))
*(argv++) = *((*Pargv)++);
/* finally, add a NULL after the last arg, like UNIX */
*argv = (char *)NULL;
/* save the values and return */
*Pargv = argvect;
*Pargc = argc;
}
static int count_args(s)
char *s;
{
int count = 0;
char ch;
do {
/* count and skip args */
++count;
while (((ch = *s) != '\0') && ch != ' ')
++s;
while (((ch = *s) != '\0') && ch == ' ')
++s;
} while (ch);
return count;
}
static void mem_err()
{
perror("Can't get memory for arguments");
exit(2);
}
#ifdef TEST
main(argc, argv)
int argc;
char **argv;
{
int i;
printf("Orig argv: %p\n", argv);
dump_args(argc, argv);
envargs(&argc, &argv, "ENVTEST");
printf(" New argv: %p\n", argv);
dump_args(argc, argv);
}
dump_args(argc, argv)
int argc;
char *argv[];
{
int i;
printf("\nDump %d args:\n", argc);
for (i = 0; i < argc; ++i)
printf("%3d %s\n", i, argv[i]);
}
#endif /* TEST */
#ifdef MSDOS /* DOS_OS2? DOS_NT_OS2? */
/*
* void mksargs(int *argcp, char ***argvp)
*
* Substitutes the extended command line argument list produced by
* the MKS Korn Shell in place of the command line info from DOS.
*
* The MKS shell gets around DOS's 128-byte limit on the length of
* a command line by passing the "real" command line in the envi-
* ronment. The "real" arguments are flagged by prepending a tilde
* (~) to each one.
*
* This "mksargs" routine creates a new argument list by scanning
* the environment from the beginning, looking for strings begin-
* ning with a tilde character. The new list replaces the original
* "argv" (pointed to by "argvp"), and the number of arguments
* in the new list replaces the original "argc" (pointed to by
* "argcp").
*
* Rich Wales
*/
void mksargs(argcp, argvp)
int *argcp;
char ***argvp;
{
#ifndef MSC /* declared differently in MSC 7.0 headers, at least */
extern char **environ; /* environment */
#endif
char **envp; /* pointer into environment */
char **newargv; /* new argument list */
char **argp; /* pointer into new arg list */
int newargc; /* new argument count */
/* sanity check */
if (environ == NULL || argcp == NULL || argvp == NULL || *argvp == NULL)
return;
/* find out how many environment arguments there are */
for (envp = environ, newargc = 0; *envp != NULL && (*envp)[0] == '~';
envp++, newargc++)
;
if (newargc == 0)
return; /* no environment arguments */
/* set up new argument list */
newargv = (char **) malloc(sizeof(char **) * (newargc+1));
if (newargv == NULL)
return; /* malloc failed */
for (argp = newargv, envp = environ; *envp != NULL && (*envp)[0] == '~';
*argp++ = &(*envp++)[1])
;
*argp = NULL; /* null-terminate the list */
/* substitute new argument list in place of old one */
*argcp = newargc;
*argvp = newargv;
}
#endif /* MSDOS */
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