source: popexec.c @ 1bb1e67

barnowl_perlaimdebianowlrelease-1.4release-1.5release-1.6release-1.7release-1.8release-1.9
Last change on this file since 1bb1e67 was 8721756, checked in by Erik Nygren <nygren@mit.edu>, 17 years ago
oops. make sure to null out reference to viewwin close hook after running it.
  • Property mode set to 100644
File size: 5.0 KB
Line 
1#include "owl.h"
2#ifdef HAVE_SYS_IOCTL_H
3#include <sys/ioctl.h>
4#endif
5#ifdef HAVE_SYS_FILIO_H
6#include <sys/filio.h>
7#endif
8#include <sys/wait.h>
9
10static const char fileIdent[] = "$Id$";
11
12/* starts up popexec in a new viewwin */
13owl_popexec *owl_popexec_new(char *command)
14{
15  owl_popexec *pe;
16  owl_popwin *pw;
17  owl_viewwin *v;
18  int pipefds[2], child_write_fd, parent_read_fd;
19  int pid;
20
21  pe = owl_malloc(sizeof(owl_popexec));
22  if (!pe) return NULL;
23  pe->winactive=0;
24  pe->pid=0;
25  pe->refcount=0;
26
27  pw=owl_global_get_popwin(&g);
28  pe->vwin=v=owl_global_get_viewwin(&g);
29
30  owl_popwin_up(pw);
31  owl_viewwin_init_text(v, owl_popwin_get_curswin(pw),
32                        owl_popwin_get_lines(pw), owl_popwin_get_cols(pw),
33                        "");
34  owl_popwin_refresh(pw);
35  owl_viewwin_redisplay(v, 0);
36  owl_global_set_needrefresh(&g);
37  owl_viewwin_set_onclose_hook(v, owl_popexec_viewwin_onclose, pe);
38  pe->refcount++;
39
40  if (0 != pipe(pipefds)) {
41    owl_function_error("owl_function_popless_exec: pipe failed\n");
42    return NULL;
43  }
44  parent_read_fd = pipefds[0];
45  child_write_fd = pipefds[1];
46  pid = fork();
47  if (pid == -1) {
48    close(pipefds[0]);
49    close(pipefds[1]);
50    owl_function_error("owl_function_popless_exec: fork failed\n");
51    return NULL;
52  } else if (pid != 0) {
53    /* still in owl */
54    int muxhandle;
55    pe->pid=pid;
56    pe->winactive=1;
57    pe->rfd = parent_read_fd;
58    close(child_write_fd);
59    muxhandle = owl_muxevents_add(owl_global_get_muxevents(&g),
60                                  parent_read_fd, OWL_MUX_READ|OWL_MUX_EXCEPT,
61                                  owl_popexec_inputhandler, (void*)pe);
62    pe->refcount++;
63  } else {
64    /* in the child process */
65    char *argv[4];
66    int i;
67    int fdlimit = sysconf(_SC_OPEN_MAX);
68
69    for (i=0; i<fdlimit; i++) {
70      if (i!=child_write_fd) close(i);
71    }
72    dup2(child_write_fd, 1 /*stdout*/);
73    dup2(child_write_fd, 2 /*stderr*/);
74    close(child_write_fd);
75   
76    while(0) {
77      write(child_write_fd, "meep\n", 5);
78      sleep(1);
79    }
80
81    argv[0] = "sh";
82    argv[1] = "-c";
83    argv[2] = command;
84    argv[3] = 0;
85    execv("/bin/sh", argv);
86    _exit(127);
87  }
88
89  return pe;
90}
91
92void owl_popexec_inputhandler(int handle, int fd, int eventmask, void *data) {
93  owl_popexec *pe = (owl_popexec*)data;
94  int navail, bread, rv_navail;
95  char *buf;
96  int status;
97
98  if (!pe) return;
99
100  /* If pe->winactive is 0 then the vwin has closed.
101   * If pe->pid is 0 then the child has already been reaped.
102   * if pe->rfd is -1 then the fd has been closed out.
103   * Under these cases we want to get to a state where:
104   *   - data read until end if child running
105   *   - child reaped
106   *   - fd closed
107   *   - callback removed
108   */
109
110  /* the viewwin has closed */
111  if (pe->rfd<0 && !pe->pid && !pe->winactive) {
112    owl_muxevents_remove(owl_global_get_muxevents(&g), handle);
113    owl_function_debugmsg("unref of %p from input handler at A", pe);
114    owl_popexec_unref(pe);
115    return;
116  }
117
118  if (0 != (rv_navail = ioctl(fd, FIONREAD, (void*)&navail))) {
119    owl_function_debugmsg("ioctl error");
120  }
121
122  /* check to see if the child has ended gracefully and no more data is
123   * ready to be read... */
124  if (navail==0 && pe->pid>0 && waitpid(pe->pid, &status, WNOHANG) > 0) {
125    owl_function_debugmsg("waitpid got child status: <%d>\n", status);
126    pe->pid = 0;
127    if (pe->winactive) { 
128      owl_viewwin_append_text(pe->vwin, "\n");
129      owl_viewwin_redisplay(pe->vwin, 1);
130    }
131    if (pe->rfd>0) {
132      close(pe->rfd);
133      pe->rfd = -1;
134    }
135    owl_muxevents_remove(owl_global_get_muxevents(&g), handle);
136    owl_function_debugmsg("unref of %p from input handler at B", pe);
137    owl_popexec_unref(pe);
138    return;
139  }
140
141  if (pe->rfd<0 || !pe->pid || !pe->winactive || rv_navail) {
142    owl_function_error("popexec should not have reached this point");
143    return;
144  }
145
146  if (navail<=0) return;
147  if (navail>1024) { navail = 1024; }
148  buf = owl_malloc(navail+1);
149  owl_function_debugmsg("about to read %d\n", navail);
150  bread = read(fd, buf, navail);
151  if (bread<0) {
152    perror("read");
153    owl_function_debugmsg("read error");
154  }
155  if (buf[navail-1] != '\0') {
156    buf[navail] = '\0';
157  }
158  owl_function_debugmsg("got data:  <%s>\n", buf);
159  if (pe->winactive) {
160    owl_viewwin_append_text(pe->vwin, buf);
161    owl_viewwin_redisplay(pe->vwin, 1);
162  }
163  owl_free(buf);
164 
165}
166
167void owl_popexec_viewwin_onclose(owl_viewwin *vwin, void *data) {
168  owl_popexec *pe = (owl_popexec*)data;
169  int status, rv;
170
171  pe->winactive = 0;
172  if (pe->rfd>0) {
173    close(pe->rfd);
174    pe->rfd = -1;
175  }
176  if (pe->pid) {
177    /* TODO: we should handle the case where SIGTERM isn't good enough */
178    rv = kill(pe->pid, SIGTERM);
179    owl_function_debugmsg("kill of pid %d returned %d", pe->pid, rv);
180    rv = waitpid(pe->pid, &status, 0);
181    owl_function_debugmsg("waidpid returned %d, status %d", rv, status);
182    pe->pid = 0;
183  }
184  owl_function_debugmsg("unref of %p from onclose", pe);
185  owl_popexec_unref(pe);
186}
187
188void owl_popexec_unref(owl_popexec *pe) {
189  owl_function_debugmsg("unref of %p was %d", pe, pe->refcount);
190  pe->refcount--;
191  if (pe->refcount<=0) {
192    owl_function_debugmsg("doing free of %p", pe);
193    owl_free(pe);
194  }
195}
Note: See TracBrowser for help on using the repository browser.