src/common/popen.c

#ifndef lint
static const char       RCSid[] = "$Id$";
#endif
/*
 * popen() and pclose() calls for systems without pipe facilities
 */
 
#include "copyright.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include "paths.h"

#ifndef NFILE
#define NFILE           32
#endif

static struct {
        char    *f;             /* file name, NULL if inactive */
        char    *c;             /* command if writing */
} pips[NFILE];


FILE *
popen(cmd, mode)                /* open command for reading or writing */
register char   *cmd;
char    *mode;
{
        FILE    *fp;
        char    *newcmd, *fname;
        register char   *cp, *cp2 = NULL;
        int     quote = '\0', paren = 0;
        
        while (isspace(*cmd))
                cmd++;
        if (!*cmd)
                return(NULL);
        fname = (char *)malloc(TEMPLEN+1);
        newcmd = (char *)malloc(TEMPLEN+6+strlen(cmd));
        if (fname == NULL | newcmd == NULL)
                return(NULL);
        mktemp(strcpy(fname,TEMPLATE));
                                /* build our command */
        for (cp = newcmd; ; cmd++) {
                switch (*cmd) {
                case '\'':
                case '"':
                        if (!quote)
                                quote = *cmd;
                        else if (quote == *cmd)
                                quote = '\0';
#ifdef MSDOS
                        else
                                break;
                        *cp++ = '"';            /* double quotes only */
                        continue;
                case '\\':
                        if (!quote && cmd[1] == '\n') {
                                *cp++ = ' ';
                                cmd++;
                                continue;
                        }
                        cmd++;
                        break;
#else
                        break;
                case '\\':
                        *cp++ = *cmd++;
                        break;
                case '(':
                        if (!quote)
                                paren++;
                        break;
                case ')':
                        if (!quote && paren)
                                paren--;
                        break;
                case ';':
#endif
                case '|':
                        if (!quote && !paren && cp2 == NULL)
                                cp2 = fname;
                        break;
                case ' ':
                case '\t':
                        if (!quote)
                                while (isspace(cmd[1]))
                                        cmd++;
                        break;
                case '\n':
                case '\0':
                        if (cp2 == NULL)
                                cp2 = fname;
                        break;
                }
                if (cp2 == fname && *mode == 'w') {     /* add input file */
                        *cp++ = ' '; *cp++ = '<';
                        while (*cp2)
                                *cp++ = *cp2++;
                        *cp++ = ' ';
                }
                if (!(*cp = *cmd))
                        break;
                cp++;
        }
        if (*mode == 'r') {                     /* add output file */
                while (isspace(cp[-1]) || cp[-1] == ';')
                        cp--;
                *cp++ = ' '; *cp++ = '>';
                while (*cp2)
                        *cp++ = *cp2++;
                *cp = '\0';
                system(newcmd);                 /* execute command first */
        }
        if ((fp = fopen(fname, mode)) == NULL) {        /* open file */
                free(fname);
                free(newcmd);
                return(NULL);
        }
        if (fileno(fp) >= NFILE) {
                eputs("popen: too many open files\n");
                quit(1);
        }
        pips[fileno(fp)].f = fname;
        if (*mode == 'r') {
                free(newcmd);
                pips[fileno(fp)].c = NULL;
        } else
                pips[fileno(fp)].c = newcmd;
        return(fp);
}


pclose(fp)                      /* close pipe and cleanup */
FILE    *fp;
{
        register int    pn = fileno(fp);

        if (pn >= NFILE || pips[pn].f == NULL || fclose(fp) == -1)
                return(-1);
        if (pips[pn].c != NULL) {
                system(pips[pn].c);             /* execute command last */
                free(pips[pn].c);
        }
        unlink(pips[pn].f);             /* remove temp file */
        free(pips[pn].f);
        pips[pn].f = NULL;
        return(0);
}
Revision:	2.6
Committed:	Tue Feb 25 02:47:21 2003 UTC (21 years, 2 months ago) by greg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rad3R6P1, rad3R5, rad3R6
Changes since 2.5:	+1 -56 lines
Log Message:	Replaced inline copyright notice with #include "copyright.h"
#	User	Rev	Content
1	greg	2.1	#ifndef lint
2	greg	2.5	static const char RCSid[] = "$Id$";
3	greg	2.1	#endif
4			/*
5			* popen() and pclose() calls for systems without pipe facilities
6			*/
7
8	greg	2.6	#include "copyright.h"
9	greg	2.5
10	greg	2.1	#include <stdio.h>
11	greg	2.5	#include <stdlib.h>
12			#include <string.h>
13	greg	2.1	#include <ctype.h>
14			#include "paths.h"
15
16			#ifndef NFILE
17			#define NFILE 32
18			#endif
19
20			static struct {
21			char f; / file name, NULL if inactive */
22			char c; / command if writing */
23			} pips[NFILE];
24
25
26			FILE *
27			popen(cmd, mode) /* open command for reading or writing */
28			register char *cmd;
29			char *mode;
30			{
31			FILE *fp;
32			char newcmd, fname;
33			register char cp, cp2 = NULL;
34			int quote = '\0', paren = 0;
35
36	greg	2.4	while (isspace(*cmd))
37			cmd++;
38			if (!*cmd)
39			return(NULL);
40	greg	2.5	fname = (char *)malloc(TEMPLEN+1);
41			newcmd = (char *)malloc(TEMPLEN+6+strlen(cmd));
42	greg	2.1	if (fname == NULL \| newcmd == NULL)
43			return(NULL);
44			mktemp(strcpy(fname,TEMPLATE));
45			/* build our command */
46			for (cp = newcmd; ; cmd++) {
47			switch (*cmd) {
48	greg	2.2	case '\'':
49	greg	2.1	case '"':
50			if (!quote)
51			quote = *cmd;
52			else if (quote == *cmd)
53			quote = '\0';
54	greg	2.2	#ifdef MSDOS
55			else
56			break;
57			cp++ = '"'; / double quotes only */
58			continue;
59	greg	2.4	case '\\':
60			if (!quote && cmd[1] == '\n') {
61			*cp++ = ' ';
62			cmd++;
63			continue;
64			}
65			cmd++;
66			break;
67	greg	2.2	#else
68	greg	2.1	break;
69	greg	2.4	case '\\':
70			cp++ = cmd++;
71			break;
72	greg	2.1	case '(':
73			if (!quote)
74			paren++;
75			break;
76			case ')':
77			if (!quote && paren)
78			paren--;
79			break;
80	greg	2.4	case ';':
81			#endif
82			case '\|':
83			if (!quote && !paren && cp2 == NULL)
84			cp2 = fname;
85	greg	2.2	break;
86			case ' ':
87			case '\t':
88			if (!quote)
89			while (isspace(cmd[1]))
90			cmd++;
91	greg	2.1	break;
92			case '\n':
93			case '\0':
94			if (cp2 == NULL)
95			cp2 = fname;
96			break;
97			}
98			if (cp2 == fname && mode == 'w') { / add input file */
99	greg	2.4	cp++ = ' '; cp++ = '<';
100	greg	2.1	while (*cp2)
101			cp++ = cp2++;
102			*cp++ = ' ';
103			}
104			if (!(cp = cmd))
105			break;
106			cp++;
107			}
108			if (mode == 'r') { / add output file */
109			while (isspace(cp[-1]) \|\| cp[-1] == ';')
110			cp--;
111	greg	2.4	cp++ = ' '; cp++ = '>';
112	greg	2.1	while (*cp2)
113			cp++ = cp2++;
114			*cp = '\0';
115			system(newcmd); /* execute command first */
116			}
117			if ((fp = fopen(fname, mode)) == NULL) { /* open file */
118			free(fname);
119			free(newcmd);
120			return(NULL);
121			}
122			if (fileno(fp) >= NFILE) {
123	greg	2.3	eputs("popen: too many open files\n");
124			quit(1);
125	greg	2.1	}
126			pips[fileno(fp)].f = fname;
127			if (*mode == 'r') {
128			free(newcmd);
129			pips[fileno(fp)].c = NULL;
130			} else
131			pips[fileno(fp)].c = newcmd;
132			return(fp);
133			}
134
135
136			pclose(fp) /* close pipe and cleanup */
137			FILE *fp;
138			{
139			register int pn = fileno(fp);
140
141			if (pn >= NFILE \|\| pips[pn].f == NULL \|\| fclose(fp) == -1)
142			return(-1);
143			if (pips[pn].c != NULL) {
144			system(pips[pn].c); /* execute command last */
145			free(pips[pn].c);
146			}
147			unlink(pips[pn].f); /* remove temp file */
148			free(pips[pn].f);
149			pips[pn].f = NULL;
150			return(0);
151			}