Add ar archive support to file.

[android-x86/external-toybox.git] / toys / posix / file.c

diff --git a/toys/posix/file.c b/toys/posix/file.c
index 0cd9047..4827f8f 100644 (file)
--- a/toys/posix/file.c
+++ b/toys/posix/file.c
@@ -3,18 +3,19 @@
  * Copyright 2016 The Android Open Source Project
  *
  * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/file.html
- *
- * TODO: ar
 
-USE_FILE(NEWTOY(file, "<1", TOYFLAG_USR|TOYFLAG_BIN))
+USE_FILE(NEWTOY(file, "<1hL[!hL]", TOYFLAG_USR|TOYFLAG_BIN))
 
 config FILE
   bool "file"
   default y
   help
-    usage: file [file...]
+    usage: file [-hL] [file...]
 
     Examine the given files and describe their content types.
+
+    -h don't follow symlinks (default)
+    -L follow symlinks
 */
 
 #define FOR_file
@@ -176,6 +177,7 @@ static void do_regular_file(int fd, char *name, struct stat *sb)
   if (len<0) perror_msg("%s", name);
 
   if (len>40 && strstart(&s, "\177ELF")) do_elf_file(fd, sb);
+  else if (len>=8 && strstart(&s, "!<arch>\n")) xprintf("ar archive\n");
   else if (len>28 && strstart(&s, "\x89PNG\x0d\x0a\x1a\x0a")) {
     // PNG is big-endian: https://www.w3.org/TR/PNG/#7Integers-and-byte-order
     int chunk_length = peek_be(s, 4);
@@ -221,24 +223,20 @@ static void do_regular_file(int fd, char *name, struct stat *sb)
     else if (toybuf[5] == '1') cpioformat = "SVR4 with no CRC";
     else if (toybuf[5] == '2') cpioformat = "SVR4 with CRC";
     xprintf("ASCII cpio archive (%s)\n", cpioformat);
-  }
-  else if (len>33 && (magic=peek(&s,2), magic==0143561 || magic==070707)) {
+  } else if (len>33 && (magic=peek(&s,2), magic==0143561 || magic==070707)) {
     if (magic == 0143561) printf("byte-swapped ");
     xprintf("cpio archive\n");
-  }
   // tar archive (ustar/pax or gnu)
-  else if (len>500 && !strncmp(s+257, "ustar", 5)) {
+  } else if (len>500 && !strncmp(s+257, "ustar", 5)) {
     xprintf("POSIX tar archive%s\n", strncmp(s+262,"  ",2)?"":" (GNU)");
-  }
   // zip/jar/apk archive, ODF/OOXML document, or such
-  else if (len>5 && strstart(&s, "PK\03\04")) {
+  } else if (len>5 && strstart(&s, "PK\03\04")) {
     int ver = (int)(char)(toybuf[4]);
     xprintf("Zip archive data");
     if (ver)
       xprintf(", requires at least v%d.%d to extract", ver/10, ver%10);
     xputc('\n');
-  }
-  else {
+  } else {
     char *what = 0;
     int i, bytes;
 
@@ -279,23 +277,22 @@ void file_main(void)
 
   // Can't use loopfiles here because it doesn't call function when can't open
   for (arg = toys.optargs; *arg; arg++) {
-    struct stat sb;
     char *name = *arg, *what = "cannot open";
+    struct stat sb;
+    int fd = !strcmp(name, "-");
 
     xprintf("%s: %*s", name, (int)(TT.max_name_len - strlen(name)), "");
 
-    if (!lstat(name, &sb)) {
-      if (S_ISFIFO(sb.st_mode)) what = "fifo";
-      else if (S_ISREG(sb.st_mode)) {
-        int fd = !strcmp(name, "-") ? 0 : open(name, O_RDONLY);
-
-        if (fd!=-1) {
-          if (!sb.st_size) what = "empty";
-          else do_regular_file(fd, name, &sb);
+    if (fd || !((toys.optflags & FLAG_L) ? stat : lstat)(name, &sb)) {
+      if (fd || S_ISREG(sb.st_mode)) {
+        if (!sb.st_size) what = "empty";
+        else if ((fd = openro(name, O_RDONLY)) != -1) {
+          do_regular_file(fd, name, &sb);
           if (fd) close(fd);
-          if (sb.st_size) continue;
+          continue;
         }
-      } else if (S_ISBLK(sb.st_mode)) what = "block special";
+      } else if (S_ISFIFO(sb.st_mode)) what = "fifo";
+      else if (S_ISBLK(sb.st_mode)) what = "block special";
       else if (S_ISCHR(sb.st_mode)) what = "character special";
       else if (S_ISDIR(sb.st_mode)) what = "directory";
       else if (S_ISSOCK(sb.st_mode)) what = "socket";