view toys/other/lspci.c @ 1572:da1bf31ed322 draft

Tweak the "ignoring return value" fortify workaround for readlinkat. We zero the buffer and if the link read fails that's left alone, so it's ok for the symlink not to be there. Unfortunately, typecasting the return value to (void) doesn't shut up gcc, and having an if(); with the semicolon on the same line doesn't shut up llvm. (The semicolon on a new line would, but C does not have significant whitespace and I'm not going to humor llvm if it plans to start.) So far, empty curly brackets consistently get the warning to shut up.
author Rob Landley <rob@landley.net>
date Mon, 24 Nov 2014 17:23:23 -0600
parents e85e5f3b87c2
children
line wrap: on
line source

/*
 * lspci - written by Isaac Dunham

USE_LSPCI(NEWTOY(lspci, "emkn"USE_LSPCI_TEXT("@i:"), TOYFLAG_USR|TOYFLAG_BIN))

config LSPCI
  bool "lspci"
  default y
  help
    usage: lspci [-ekm]

    List PCI devices.

    -e	Print all 6 digits in class
    -k	Print kernel driver
    -m	Machine parseable format

config LSPCI_TEXT
  bool "lspci readable output"
  depends on LSPCI
  default y
  help
    usage: lspci [-n] [-i FILE ]

    -n	Numeric output (repeat for readable and numeric)
    -i	PCI ID database (default /usr/share/misc/pci.ids)

*/

#define FOR_lspci
#include "toys.h"

GLOBALS(
  char *ids;
  long numeric;

  FILE *db;
)

int do_lspci(struct dirtree *new)
{
  char *p = toybuf, *vendor = toybuf+9, *device = toybuf+18,
       driver[256], *vbig = 0, *dbig = 0, **fields;
  int dirfd;

  if (!new->parent) return DIRTREE_RECURSE;

  // Parse data out of /proc

  if (-1 == (dirfd = openat(dirtree_parentfd(new), new->name, O_RDONLY)))
    return 0;

  // it's ok for the driver link not to be there, whatever fortify says
  *driver = 0;
  if (toys.optflags & FLAG_k)
    if (readlinkat(dirfd, "driver", driver, sizeof(driver))) {};

  for (fields = (char*[]){"class", "vendor", "device", 0}; *fields; fields++) {
    int fd, size = 6 + 2*((toys.optflags & FLAG_e) && p == toybuf);
    *p = 0;

    if (-1 == (fd = openat(dirfd, *fields, O_RDONLY))) {
      close(dirfd);
      return 0;
    }
    xreadall(fd, p, size);
    memmove(p, p+2, size -= 2);
    p[size] = 0;
    close(fd);
    p += 9;
  }

  close(dirfd);

  // Lookup/display data from pci.ids?

  if (CFG_LSPCI_TEXT && TT.db) {
    if (TT.numeric != 1) {
      char *s;

      fseek(TT.db, 0, SEEK_SET);
      while (!vbig || !dbig) {
        s = p;
        if (!fgets(s, sizeof(toybuf)-(p-toybuf)-1, TT.db)) break;
        while (isspace(*s)) s++;
        if (*s == '#') continue;
        if (vbig && s == p) break;
        if (strstart(&s, vbig ? device : vendor)) {
          if (vbig) dbig = s+2;
          else vbig = s+2;
          s += strlen(s);
          s[-1] = 0; // trim ending newline
          p = s + 1;
        }
      }
    }

    if (TT.numeric > 1) {
      printf((toys.optflags & FLAG_m)
        ? "%s, \"%s\" \"%s [%s]\" \"%s [%s]\""
        : "%s Class %s: %s [%s] %s [%s]",
        new->name+5, toybuf, vbig ? vbig : "", vendor,
        dbig ? dbig : "", device);

      goto driver;
    }
  }

  printf((toys.optflags & FLAG_m) ? "%s \"%s\" \"%s\" \"%s\""
    : "%s Class %s: %s:%s", new->name+5, toybuf, 
    vbig ? vbig : vendor, dbig ? dbig : device);

driver:
  if (*driver)
    printf((toys.optflags & FLAG_m) ? " \"%s\"" : " %s", basename(driver));
  xputc('\n');

  return 0;
}

void lspci_main(void)
{
  if (CFG_LSPCI_TEXT && TT.numeric != 1) {
    if (!TT.ids) TT.ids = "/usr/share/misc/pci.ids";
    if (!(TT.db = fopen(TT.ids, "r")))
      perror_msg("could not open PCI ID db");
  }

  dirtree_read("/sys/bus/pci/devices", do_lspci);
}