ref: f5b8cc5fd4531d9f5719f64eff4133fbdf0fc749
parent: 89500cba40332128f191a2403ea2c1b7c647d5e8
author: aiju <[email protected]>
date: Sun Jun 26 11:20:45 EDT 2011
added pstree
--- /dev/null
+++ b/sys/src/cmd/pstree.c
@@ -1,0 +1,189 @@
+#include <u.h>
+#include <libc.h>
+
+enum { NBUCKETS = 1024 };+
+typedef struct Proc Proc;
+typedef struct Bucket Bucket;
+
+struct Proc {+ int pid;
+ Proc *first, *last, *parent, *next;
+ Proc *bnext;
+};
+
+struct Bucket {+ Proc *first, *last;
+} buck[NBUCKETS];
+
+Proc *
+getproc(int pid)
+{+ Proc *p;
+
+ for(p = buck[pid % NBUCKETS].first; p; p = p->next)
+ if(p->pid == pid)
+ return p;
+
+ return nil;
+}
+
+void
+addproc(int pid)
+{+ Proc *p;
+ Bucket *b;
+
+ p = mallocz(sizeof(*p), 1);
+ if(p == nil)
+ sysfatal("malloc: %r");+ p->pid = pid;
+ b = buck + pid % NBUCKETS;
+ if(b->first != nil)
+ b->last->bnext = p;
+ else
+ b->first = p;
+ b->last = p;
+}
+
+int
+theppid(int pid)
+{+ char *file;
+ int fd;
+ char buf[12];
+ int ppid;
+
+ file = smprint("/proc/%d/ppid", pid);+ fd = open(file, OREAD);
+ free(file);
+ if(fd < 0)
+ return 0;
+ ppid = 0;
+ if(read(fd, buf, sizeof buf) >= 0)
+ ppid = atoi(buf);
+ close(fd);
+ return ppid;
+}
+
+void
+addppid(int pid)
+{+ int ppid;
+ Proc *p, *par;
+
+ p = getproc(pid);
+ ppid = theppid(pid);
+ par = getproc(ppid);
+ if(par == nil)
+ par = getproc(0);
+ p->parent = par;
+ if(par->first != nil)
+ par->last->next = p;
+ else
+ par->first = p;
+ par->last = p;
+}
+
+void
+addprocs(void)
+{+ int fd, rc, i;
+ Dir *d;
+
+ fd = open("/proc", OREAD);+ if(fd < 0)
+ sysfatal("open: %r");+ rc = dirreadall(fd, &d);
+ if(rc < 0)
+ sysfatal("dirreadall: %r");+ close(fd);
+ for(i = 0; i < rc; i++)
+ if(d[i].mode & DMDIR)
+ addproc(atoi(d[i].name));
+ for(i = 0; i < rc; i++)
+ if(d[i].mode & DMDIR)
+ addppid(atoi(d[i].name));
+ free(d);
+}
+
+Rune buf[512];
+
+int
+readout(char *file)
+{+ int fd, rc, n;
+ char b[512];
+
+ fd = open(file, OREAD);
+ free(file);
+ if(fd < 0)
+ return -1;
+ n = 0;
+ while(rc = read(fd, b, 512), rc > 0) {+ write(1, b, rc);
+ n += rc;
+ }
+ close(fd);
+ return n;
+}
+
+void
+printargs(int pid)
+{+ char *file;
+ char b[28], *p;
+ int fd;
+
+ if(pid == 0)
+ return;
+ if(readout(smprint("/proc/%d/args", pid)) > 0)+ return;
+ file = smprint("/proc/%d/status", pid);+ fd = open(file, OREAD);
+ free(file);
+ if(fd < 0)
+ return;
+ memset(b, 0, sizeof b);
+ if(read(fd, b, 27) <= 0)
+ return;
+ p = b + strlen(b) - 1;
+ while(*p == ' ')
+ *p-- = 0;
+ print("%s", b);+}
+
+void
+descend(Proc *p, Rune *r)
+{+ Rune last;
+ Proc *q;
+
+ last = *--r;
+ *r = last == L' ' ? L'└' : L'├';
+ print("%S", buf);+ printargs(p->pid);
+ print(" [%d]\n", p->pid);+ *r = last;
+ *++r = L'│';
+ for(q = p->first; q; q = q->next) {+ if(q->next == nil)
+ *r = L' ';
+ descend(q, r + 1);
+ }
+ *r = 0;
+}
+
+void
+printprocs(void)
+{+ descend(getproc(0), buf);
+}
+
+void
+main()
+{+ addproc(0);
+ addprocs();
+ printprocs();
+}