Adding upstream version 2:4.0.4.upstream/2%4.0.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 364 insertions, 0 deletions

diff --git a/library/devname.c b/library/devname.c
new file mode 100644
index 0000000..6a23653
--- /dev/null
+++ b/library/devname.c
@@ -0,0 +1,364 @@
+/*
+ * devname - device name functions
+ *
+ * Copyright © 2011-2023 Jim Warner <james.warner@comcast.net>
+ * Copyright © 2017-2023 Craig Small <csmall@dropbear.xyz>
+ * Copyright © 1998-2009 Albert Cahalan
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include "misc.h"
+#include "devname.h"
+
+// This is the buffer size for a tty name. Any path is legal,
+// which makes PAGE_SIZE appropriate (see kernel source), but
+// that is only 99% portable and utmp only holds 32 anyway.
+// We need at least 20 for guess_name().
+#define TTY_NAME_SIZE 128
+
+/* Who uses what:
+ *
+ * dev_to_tty   top, ps
+ */
+
+#ifdef MAJOR_IN_MKDEV
+#include <sys/mkdev.h>
+#elif defined MAJOR_IN_SYSMACROS
+#include <sys/sysmacros.h>
+#else
+#define major(d) ( ((unsigned)(d)>>8u) & 0xfffu )
+#define minor(d) ( ((unsigned)(d)&0xffu) | (((unsigned)(d)&0xfff00000u)>>12u) )
+#endif
+
+typedef struct tty_map_node {
+  struct tty_map_node *next;
+  unsigned short devfs_type;  // bool
+  unsigned short major_number;
+  unsigned minor_first;
+  unsigned minor_last;
+  char name[16];
+} tty_map_node;
+
+static __thread tty_map_node *tty_map = NULL;
+
+/* Load /proc/tty/drivers for device name mapping use. */
+static void load_drivers(void){
+  char buf[10000];
+  char *p;
+  int fd;
+  int bytes;
+  fd = open("/proc/tty/drivers",O_RDONLY);
+  if(fd == -1) goto fail;
+  bytes = read(fd, buf, sizeof(buf) - 1);
+  if(bytes == -1) goto fail;
+  buf[bytes] = '\0';
+  p = buf;
+  while(( p = strstr(p, " /dev/") )){  // " /dev/" is the second column
+    tty_map_node *tmn;
+    size_t len;
+    char *end;
+    p += 6;
+    end = strchr(p, ' ');
+    if(!end) continue;
+    len = end - p;
+    if (!(tmn = calloc(1, sizeof(tty_map_node))))
+       goto fail;
+    tmn->next = tty_map;
+    tty_map = tmn;
+    /* if we have a devfs type name such as /dev/tts/%d then strip the %d but
+       keep a flag. */
+    if(len >= 3 && !strncmp(end - 2, "%d", 2)){
+      len -= 2;
+      tmn->devfs_type = 1;
+    }
+    if(len >= sizeof tmn->name)
+      len = sizeof tmn->name - 1; // mangle it to avoid overflow
+    memcpy(tmn->name, p, len);
+    p = end; /* set p to point past the %d as well if there is one */
+    while(*p == ' ') p++;
+    tmn->major_number = atoi(p);
+    p += strspn(p, "0123456789");
+    while(*p == ' ') p++;
+    switch(sscanf(p, "%u-%u", &tmn->minor_first, &tmn->minor_last)){
+    default:
+      /* Can't finish parsing this line so we remove it from the list */
+      tty_map = tty_map->next;
+      free(tmn);
+      break;
+    case 1:
+      tmn->minor_last = tmn->minor_first;
+      break;
+    case 2:
+      break;
+    }
+  }
+fail:
+  if(fd != -1) close(fd);
+  if(!tty_map) tty_map = (tty_map_node *)-1;
+}
+
+/* Try to guess the device name from /proc/tty/drivers info. */
+static int driver_name(char *restrict const buf, unsigned maj, unsigned min){
+  struct stat sbuf;
+  tty_map_node *tmn;
+  if(!tty_map) load_drivers();
+  if(tty_map == (tty_map_node *)-1) return 0;
+  tmn = tty_map;
+  for(;;){
+    if(!tmn) return 0;
+    if(tmn->major_number == maj && tmn->minor_first <= min && tmn->minor_last >= min) break;
+    tmn = tmn->next;
+  }
+  sprintf(buf, "/dev/%s%d", tmn->name, min);  /* like "/dev/ttyZZ255" */
+  if(stat(buf, &sbuf) < 0){
+    sprintf(buf, "/dev/%s/%d", tmn->name, min);  /* like "/dev/pts/255" */
+    if(stat(buf, &sbuf) < 0){
+      if(tmn->devfs_type) return 0;
+      sprintf(buf, "/dev/%s", tmn->name);  /* like "/dev/ttyZZ255" */
+      if(stat(buf, &sbuf) < 0) return 0;
+    }
+  }
+  if(min != minor(sbuf.st_rdev)) return 0;
+  if(maj != major(sbuf.st_rdev)) return 0;
+  return 1;
+}
+
+// major 204 is a mess -- "Low-density serial ports"
+static const char low_density_names[][6] = {
+"LU0",  "LU1",  "LU2",  "LU3",
+"FB0",
+"SA0",  "SA1",  "SA2",
+"SC0",  "SC1",  "SC2",  "SC3",
+"FW0",  "FW1",  "FW2",  "FW3",
+"AM0",  "AM1",  "AM2",  "AM3",  "AM4",  "AM5",  "AM6",  "AM7",
+"AM8",  "AM9",  "AM10", "AM11", "AM12", "AM13", "AM14", "AM15",
+"DB0",  "DB1",  "DB2",  "DB3",  "DB4",  "DB5",  "DB6",  "DB7",
+"SG0",
+"SMX0",  "SMX1",  "SMX2",
+"MM0",  "MM1",
+"CPM0", "CPM1", "CPM2", "CPM3", /* "CPM4", "CPM5", */  // bad allocation?
+"IOC0",  "IOC1",  "IOC2",  "IOC3",  "IOC4",  "IOC5",  "IOC6",  "IOC7",
+"IOC8",  "IOC9",  "IOC10", "IOC11", "IOC12", "IOC13", "IOC14", "IOC15",
+"IOC16", "IOC17", "IOC18", "IOC19", "IOC20", "IOC21", "IOC22", "IOC23",
+"IOC24", "IOC25", "IOC26", "IOC27", "IOC28", "IOC29", "IOC30", "IOC31",
+"VR0", "VR1",
+"IOC84",  "IOC85",  "IOC86",  "IOC87",  "IOC88",  "IOC89",  "IOC90",  "IOC91",
+"IOC92",  "IOC93",  "IOC94", "IOC95", "IOC96", "IOC97", "IOC98", "IOC99",
+"IOC100", "IOC101", "IOC102", "IOC103", "IOC104", "IOC105", "IOC106", "IOC107",
+"IOC108", "IOC109", "IOC110", "IOC111", "IOC112", "IOC113", "IOC114", "IOC115",
+"SIOC0",  "SIOC1",  "SIOC2",  "SIOC3",  "SIOC4",  "SIOC5",  "SIOC6",  "SIOC7",
+"SIOC8",  "SIOC9",  "SIOC10", "SIOC11", "SIOC12", "SIOC13", "SIOC14", "SIOC15",
+"SIOC16", "SIOC17", "SIOC18", "SIOC19", "SIOC20", "SIOC21", "SIOC22", "SIOC23",
+"SIOC24", "SIOC25", "SIOC26", "SIOC27", "SIOC28", "SIOC29", "SIOC30", "SIOC31",
+"PSC0", "PSC1", "PSC2", "PSC3", "PSC4", "PSC5",
+"AT0",  "AT1",  "AT2",  "AT3",  "AT4",  "AT5",  "AT6",  "AT7",
+"AT8",  "AT9",  "AT10", "AT11", "AT12", "AT13", "AT14", "AT15",
+"NX0",  "NX1",  "NX2",  "NX3",  "NX4",  "NX5",  "NX6",  "NX7",
+"NX8",  "NX9",  "NX10", "NX11", "NX12", "NX13", "NX14", "NX15",
+"J0",   // minor is 186
+"UL0","UL1","UL2","UL3",
+"xvc0", // FAIL -- "/dev/xvc0" lacks "tty" prefix
+"PZ0","PZ1","PZ2","PZ3",
+"TX0","TX1","TX2","TX3","TX4","TX5","TX6","TX7",
+"SC0","SC1","SC2","SC3",
+"MAX0","MAX1","MAX2","MAX3",
+};
+
+#if 0
+// test code
+#include <stdio.h>
+#define AS(x) (sizeof(x)/sizeof((x)[0]))
+int main(int argc, char *argv[]){
+  int i = 0;
+  while(i<AS(low_density_names)){
+    printf("%3d = /dev/tty%.*s\n",i,sizeof low_density_names[i],low_density_names[i]);
+    i++;
+  }
+  return 0;
+}
+#endif
+
+/* Try to guess the device name (useful until /proc/PID/tty is added) */
+static int guess_name(char *restrict const buf, unsigned maj, unsigned min){
+  struct stat sbuf;
+#ifndef __CYGWIN__
+  int t0, t1;
+#endif
+  unsigned tmpmin = min;
+
+  switch(maj){
+  case   3:      /* /dev/[pt]ty[p-za-o][0-9a-z] is 936 */
+    if(tmpmin > 255) return 0;   // should never happen; array index protection
+#ifdef __CYGWIN__
+    sprintf(buf, "cons%d", tmpmin);
+    /* Skip stat call.  The reason is that cons devices are local to
+     * the processes running in that console.  Calling stat from another
+     * console or pty will return -1. */
+   return 1;
+#else
+    t0 = "pqrstuvwxyzabcde"[tmpmin>>4];
+    t1 = "0123456789abcdef"[tmpmin&0x0f];
+    sprintf(buf, "/dev/tty%c%c", t0, t1);
+#endif
+    break;
+  case   4:
+    if(min<64){
+      sprintf(buf, "/dev/tty%d", min);
+      break;
+    }
+    sprintf(buf, "/dev/ttyS%d", min-64);
+    break;
+  case  11:  sprintf(buf, "/dev/ttyB%d",  min); break;
+  case  17:  sprintf(buf, "/dev/ttyH%d",  min); break;
+  case  19:  sprintf(buf, "/dev/ttyC%d",  min); break;
+  case  22:  sprintf(buf, "/dev/ttyD%d",  min); break; /* devices.txt */
+  case  23:  sprintf(buf, "/dev/ttyD%d",  min); break; /* driver code */
+  case  24:  sprintf(buf, "/dev/ttyE%d",  min); break;
+  case  32:  sprintf(buf, "/dev/ttyX%d",  min); break;
+  case  43:  sprintf(buf, "/dev/ttyI%d",  min); break;
+  case  46:  sprintf(buf, "/dev/ttyR%d",  min); break;
+  case  48:  sprintf(buf, "/dev/ttyL%d",  min); break;
+  case  57:  sprintf(buf, "/dev/ttyP%d",  min); break;
+  case  71:  sprintf(buf, "/dev/ttyF%d",  min); break;
+  case  75:  sprintf(buf, "/dev/ttyW%d",  min); break;
+  case  78:  sprintf(buf, "/dev/ttyM%d",  min); break; /* conflict */
+  case 105:  sprintf(buf, "/dev/ttyV%d",  min); break;
+  case 112:  sprintf(buf, "/dev/ttyM%d",  min); break; /* conflict */
+#ifdef __CYGWIN__
+  case 136:  sprintf(buf, "/dev/pty%d",   min); break;
+#else
+  /* 136 ... 143 are /dev/pts/0, /dev/pts/1, /dev/pts/2 ... */
+  case 136 ... 143:  sprintf(buf, "/dev/pts/%d",  min+(maj-136)*256); break;
+#endif
+  case 148:  sprintf(buf, "/dev/ttyT%d",  min); break;
+  case 154:  sprintf(buf, "/dev/ttySR%d", min); break;
+  case 156:  sprintf(buf, "/dev/ttySR%d", min+256); break;
+  case 164:  sprintf(buf, "/dev/ttyCH%d",  min); break;
+  case 166:  sprintf(buf, "/dev/ttyACM%d", min); break; /* bummer, 9-char */
+  case 172:  sprintf(buf, "/dev/ttyMX%d",  min); break;
+  case 174:  sprintf(buf, "/dev/ttySI%d",  min); break;
+  case 188:  sprintf(buf, "/dev/ttyUSB%d", min); break; /* bummer, 9-char */
+  case 204:
+    if(min >= sizeof low_density_names / sizeof low_density_names[0]) return 0;
+    memcpy(buf,"/dev/tty",8);
+    memcpy(buf+8, low_density_names[min], sizeof low_density_names[0]);
+    buf[8 + sizeof low_density_names[0]] = '\0';
+//    snprintf(buf, 9 + sizeof low_density_names[0], "/dev/tty%.*s", sizeof low_density_names[0], low_density_names[min]);
+    break;
+  case 208:  sprintf(buf, "/dev/ttyU%d",  min); break;
+  case 216:  sprintf(buf, "/dev/ttyUB%d",  min); break; // "/dev/rfcomm%d" now?
+  case 224:  sprintf(buf, "/dev/ttyY%d",  min); break;
+  case 227:  sprintf(buf, "/dev/3270/tty%d", min); break; /* bummer, HUGE */
+  case 229:  sprintf(buf, "/dev/iseries/vtty%d",  min); break; /* bummer, HUGE */
+  case 256:  sprintf(buf, "/dev/ttyEQ%d",  min); break;
+  default: return 0;
+  }
+  if(stat(buf, &sbuf) < 0) return 0;
+  if(min != minor(sbuf.st_rdev)) return 0;
+  if(maj != major(sbuf.st_rdev)) return 0;
+  return 1;
+}
+
+/* Linux 2.2 can give us filenames that might be correct.
+ * Useful names could be in /proc/PID/fd/2 (stderr, seldom redirected)
+ * and in /proc/PID/fd/255 (used by bash to remember the tty).
+ */
+static int link_name(char *restrict const buf, unsigned maj, unsigned min, int pid, const char *restrict name){
+  struct stat sbuf;
+  char path[32];
+  ssize_t count;
+  const int len = snprintf(path, sizeof path, "/proc/%d/%s", pid, name);  /* often permission denied */
+  if(len <= 0 || (size_t)len >= sizeof path) return 0;
+  count = readlink(path,buf,TTY_NAME_SIZE-1);
+  if(count <= 0 || count >= TTY_NAME_SIZE-1) return 0;
+  buf[count] = '\0';
+  if(stat(buf, &sbuf) < 0) return 0;
+  if(min != minor(sbuf.st_rdev)) return 0;
+  if(maj != major(sbuf.st_rdev)) return 0;
+  return 1;
+}
+
+#ifdef USE_PROC_CTTY
+/* Cygwin keeps the name to the controlling tty in a virtual file called
+   /proc/PID/ctty, including a trailing LF (sigh). */
+static int ctty_name(char *restrict const buf, int pid) {
+  char path[32];
+  FILE *fp;
+  char *lf;
+  sprintf (path, "/proc/%d/ctty", pid);  /* often permission denied */
+  fp = fopen (path, "r");
+  if (!fp)
+    return 0;
+  if (!fgets (buf,TTY_NAME_SIZE,fp))
+    {
+      fclose (fp);
+      return 0;
+    }
+  fclose (fp);
+  lf = strchr (buf, '\n');
+  if (lf)
+    *lf = (lf == buf ? '?' : '\0');
+  return 1;
+}
+#endif
+
+/* number --> name */
+unsigned dev_to_tty(char *restrict ret, unsigned chop, dev_t dev_t_dev, int pid, unsigned int flags) {
+  static __thread char buf[TTY_NAME_SIZE];
+  char *restrict tmp = buf;
+  unsigned dev = dev_t_dev;
+  unsigned i = 0;
+  int c;
+#ifdef USE_PROC_CTTY
+  if(  ctty_name(tmp, pid                                        )) goto abbrev;
+#endif
+  if(dev == 0u) goto no_tty;
+  if(driver_name(tmp, major(dev), minor(dev)               )) goto abbrev;
+  if(  link_name(tmp, major(dev), minor(dev), pid, "fd/2"  )) goto abbrev;
+  if( guess_name(tmp, major(dev), minor(dev)               )) goto abbrev;
+  if(  link_name(tmp, major(dev), minor(dev), pid, "fd/255")) goto abbrev;
+  // fall through if unable to find a device file
+no_tty:
+  strcpy(ret, chop >= 1 ? "?" : "");
+  return 1;
+abbrev:
+  if((flags&ABBREV_DEV) && !strncmp(tmp,"/dev/",5) && tmp[5]) tmp += 5;
+  if((flags&ABBREV_TTY) && !strncmp(tmp,"tty",  3) && tmp[3]) tmp += 3;
+  if((flags&ABBREV_PTS) && !strncmp(tmp,"pts/", 4) && tmp[4]) tmp += 4;
+  /* gotta check before we chop or we may chop someone else's memory */
+  if(chop + (unsigned long)(tmp-buf) < sizeof buf)
+    tmp[chop] = '\0';
+  /* replace non-ASCII characters with '?' and return the number of chars */
+  while(i < chop){
+    c = *tmp;
+    tmp++;
+    if(!c) break;
+    i++;
+    if(c<=' ') c = '?';
+    if(c>126)  c = '?';
+    *ret = c;
+    ret++;
+  }
+  *ret = '\0';
+  return i;
+}