lsof cleanup

Accept multiple -p, inline filter_matches, convert misleading "char* a, b" to
"char *a, b", use readfile() to read a file, use DIRTREE_SHUTUP, don't need
{ } around a single line, don't modify command line environment space
(which changes what ps/pgrep sees).

toys/pending/lsof.c

@@ -2,7 +2,7 @@
  *
  * Copyright 2015 The Android Open Source Project
 
-USE_LSOF(NEWTOY(lsof, "lp:t", TOYFLAG_USR|TOYFLAG_BIN))
+USE_LSOF(NEWTOY(lsof, "lp*t", TOYFLAG_USR|TOYFLAG_BIN))
 
 config LSOF
  bool "lsof"
@@ -22,7 +22,7 @@ config LSOF
 #include "toys.h"
 
 GLOBALS(
- char *pids;
+ struct arg_list *p;
 
  struct stat *sought_files;
 
@@ -42,30 +42,14 @@ struct file_info {
 
  // For output.
  struct proc_info pi;
- char fd[8];
- char rw;
- char locks;
- char type[10];
- char device[32];
- char size_off[32];
- char node[32];
  char* name;
+ char fd[8], rw, locks, type[10], device[32], size_off[32], node[32];
 
  // For filtering.
  dev_t st_dev;
  ino_t st_ino;
 };
 
-static int filter_matches(struct file_info *fi)
-{
- struct stat *sb = TT.sought_files;
-
- for (; sb != &(TT.sought_files[toys.optc]); ++sb) {
- if (sb->st_dev == fi->st_dev && sb->st_ino == fi->st_ino) return 1;
- }
- return 0;
-}
-
 static void print_header()
 {
  // TODO: llist_traverse to measure the columns first.
@@ -81,11 +65,20 @@ static void print_info(void *data)
 {
  struct file_info *fi = data;
 
- if (toys.optc && !filter_matches(fi)) return;
+ // Filter matches
+ if (toys.optc) {
+ int i;
+
+ for (i = 0; i<toys.optc; i++)
+ if (TT.sought_files[i].st_dev==fi->st_dev)
+ if (TT.sought_files[i].st_ino==fi->st_ino) break;
+
+ if (i==toys.optc) return;
+ }
 
  if (toys.optflags&FLAG_t) {
  if (fi->pi.pid != TT.last_shown_pid)
- printf("%d\n", (TT.last_shown_pid = fi->pi.pid));
+ printf("%d\n", TT.last_shown_pid = fi->pi.pid);
  } else {
  if (!TT.shown_header) print_header();
  printf("%-9s %5d %10.10s %4s%c%c %7s %18s %9s %10s %s\n",
@@ -242,7 +235,7 @@ static int find_socket(struct file_info *fi, long inode)
  scan_proc_net_file("/proc/net/netlink", 0, 0, match_netlink, fi, inode);
 }
 
-static void fill_stat(struct file_info *fi, const char* path)
+static void fill_stat(struct file_info *fi, const char *path)
 {
  struct stat sb;
  long dev;
@@ -284,7 +277,7 @@ static void fill_stat(struct file_info *fi, const char* path)
  fi->st_ino = sb.st_ino;
 }
 
-struct file_info *new_file_info(struct proc_info *pi, const char* fd)
+struct file_info *new_file_info(struct proc_info *pi, const char *fd)
 {
  struct file_info *fi = xzalloc(sizeof(struct file_info));
 
@@ -300,7 +293,7 @@ struct file_info *new_file_info(struct proc_info *pi, const char* fd)
  return fi;
 }
 
-static void visit_symlink(struct proc_info *pi, char* name, char* path)
+static void visit_symlink(struct proc_info *pi, char *name, char *path)
 {
  struct file_info *fi = new_file_info(pi, "");
 
@@ -382,19 +375,15 @@ static void visit_fds(struct proc_info *pi)
 static void lsof_pid(int pid)
 {
  struct proc_info pi;
- FILE *fp;
  char *line;
  struct stat sb;
 
- // Does this process even exist?
- snprintf(toybuf, sizeof(toybuf), "/proc/%d/stat", pid);
- fp = fopen(toybuf, "r");
- if (!fp) return;
+ // Skip nonexistent pids
+ sprintf(toybuf, "/proc/%d/stat", pid);
+ if (!(line = readfile(toybuf, toybuf, sizeof(toybuf)))) return;
 
  // Get COMMAND.
  strcpy(pi.cmd, "?");
- line = fgets(toybuf, sizeof(toybuf), fp);
- fclose(fp);
  if (line) {
  char *open_paren = strchr(toybuf, '(');
  char *close_paren = strrchr(toybuf, ')');
@@ -429,31 +418,33 @@ static int scan_slash_proc(struct dirtree *node)
 {
  int pid;
 
- if (!node->parent) return DIRTREE_RECURSE;
+ if (!node->parent) return DIRTREE_RECURSE|DIRTREE_SHUTUP;
  if ((pid = atol(node->name))) lsof_pid(pid);
+
  return 0;
 }
 
 void lsof_main(void)
 {
+ struct arg_list *pp;
  int i;
 
  // lsof will only filter on paths it can stat (because it filters by inode).
  TT.sought_files = xmalloc(toys.optc*sizeof(struct stat));
- for (i = 0; i < toys.optc; ++i) {
- xstat(toys.optargs[i], &(TT.sought_files[i]));
- }
+ for (i = 0; i<toys.optc; ++i) xstat(toys.optargs[i], TT.sought_files+i);
 
- if (toys.optflags&FLAG_p) {
- char *pid_str;
+ if (!TT.p) dirtree_read("/proc", scan_slash_proc);
+ else for (pp = TT.p; pp; pp = pp->next) {
+ char *start, *end, *next = pp->arg;
  int length, pid;
 
- while ((pid_str = comma_iterate(&TT.pids, &length))) {
- pid_str[length] = 0;
- if (!(pid = atoi(pid_str))) error_exit("bad pid '%s'", pid_str);
+ while ((start = comma_iterate(&next, &length))) {
+ pid = strtol(start, &end, 10);
+ if (pid<1 || (*end && *end!=','))
+ error_exit("bad -p '%.*s'", (int)(end-start), start);
  lsof_pid(pid);
  }
- } else dirtree_read("/proc", scan_slash_proc);
+ }
 
  llist_traverse(TT.files, print_info);
 }