initial commit

1 files changed, 515 insertions, 0 deletions

diff --git a/src/skaembutils/s6-test.c b/src/skaembutils/s6-test.c
new file mode 100644
index 0000000..3dda0b7
--- /dev/null
+++ b/src/skaembutils/s6-test.c
@@ -0,0 +1,515 @@
+/* ISC license. */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <skalibs/uint.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/fmtscan.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/djbunix.h>
+
+#define USAGE "s6-test expression  or  [ expression ]"
+
+enum opnum
+{
+  T_NOT,
+  T_AND,
+  T_OR,
+  T_LEFTP,
+  T_RIGHTP,
+  T_BLOCK,
+  T_CHAR,
+  T_DIR,
+  T_EXIST,
+  T_REGULAR,
+  T_SGID,
+  T_SYMLINK,
+  T_STICKY,
+  T_NONZERO,
+  T_FIFO,
+  T_READABLE,
+  T_NONZEROFILE,
+  T_TERM,
+  T_SUID,
+  T_WRITABLE,
+  T_EXECUTABLE,
+  T_ZERO,
+  T_EUID,
+  T_EGID,
+  T_SOCKET,
+  T_MODIFIED,
+  T_NEWER,
+  T_OLDER,
+  T_DEVINO,
+  T_STREQUAL,
+  T_STRNEQUAL,
+  T_STRLESSER,
+  T_STRLESSERE,
+  T_STRGREATER,
+  T_STRGREATERE,
+  T_NUMEQUAL,
+  T_NUMNEQUAL,
+  T_NUMGREATER,
+  T_NUMGREATERE,
+  T_NUMLESSER,
+  T_NUMLESSERE
+} ;
+
+struct token
+{
+  char const *string ;
+  enum opnum op ;
+  unsigned int type ;
+} ;
+
+struct node
+{
+  enum opnum op ;
+  unsigned int type ;
+  unsigned int arg1 ;
+  unsigned int arg2 ;
+  char const *data ;
+} ;
+
+static unsigned int lex (struct node *tree, char const *const *argv)
+{
+  static struct token const tokens[44] =
+  {
+    { "-n", T_NONZERO, 2 },
+    { "-z", T_ZERO, 2 },
+    { "=", T_STREQUAL, 3 },
+    { "!=", T_STRNEQUAL, 3 },
+    { "-eq", T_NUMEQUAL, 3 },
+    { "-ne", T_NUMNEQUAL, 3 },
+    { "-gt", T_NUMGREATER, 3 },
+    { "-ge", T_NUMGREATERE, 3 },
+    { "-lt", T_NUMLESSER, 3 },
+    { "-le", T_NUMLESSERE, 3 },
+    { "-f", T_REGULAR, 2 },
+    { "-h", T_SYMLINK, 2 },
+    { "-L", T_SYMLINK, 2 },
+    { "-e", T_EXIST, 2 },
+    { "-k", T_STICKY, 2 },
+    { "-a", T_AND, 7 },
+    { "-o", T_OR, 8 },
+    { "!", T_NOT, 6 },
+    { "(", T_LEFTP, 4 },
+    { ")", T_RIGHTP, 5 },
+    { "-b", T_BLOCK, 2 },
+    { "-c", T_CHAR, 2 },
+    { "-d", T_DIR, 2 },
+    { "-g", T_SGID, 2 },
+    { "-p", T_FIFO, 2 },
+    { "-r", T_READABLE, 2 },
+    { "-s", T_NONZEROFILE, 2 },
+    { "-t", T_TERM, 2 },
+    { "-u", T_SUID, 2 },
+    { "-w", T_WRITABLE, 2 },
+    { "-x", T_EXECUTABLE, 2 },
+    { "-O", T_EUID, 2 },
+    { "-U", T_EUID, 2 },
+    { "-G", T_EGID, 2 },
+    { "-S", T_SOCKET, 2 },
+    { "-N", T_MODIFIED, 2 },
+    { "-nt", T_NEWER, 3 },
+    { "-ot", T_OLDER, 3 },
+    { "-ef", T_DEVINO, 3 },
+    { "<", T_STRLESSER, 3 },
+    { "<=", T_STRLESSERE, 3 },
+    { ">", T_STRGREATER, 3 },
+    { ">=", T_STRGREATERE, 3 },
+    { 0, 0, 0 }
+  } ;
+  register unsigned int pos = 0 ;
+
+  for (; argv[pos] ; pos++)
+  {
+    unsigned int i = 0 ;
+    tree[pos].data = argv[pos] ;
+    for (i = 0 ; tokens[i].string ; i++)
+      if (!str_diff(argv[pos], tokens[i].string))
+      {
+        tree[pos].op = tokens[i].op ;
+        tree[pos].type = tokens[i].type ;
+        break ;
+      }
+    if (!tokens[i].string)
+    {
+      tree[pos].op = T_NONZERO ;
+      tree[pos].type = 0 ;
+      tree[pos].arg1 = pos ;
+      if (*(argv[pos]) == '\\') tree[pos].data++ ; /* better than SUSv3 */
+    }
+  }
+  return pos ;
+}
+
+static unsigned int parse (struct node *tree, unsigned int n)
+{
+  static char const table[9][13] =
+  {
+    "xssssxsssxxxx",
+    "xxxxxaxxxxxxx",
+    "xsxxsxsssxxxx",
+    "sxxxxxxxxxxxx",
+    "xsxxsxsssxxxx",
+    "nxxxxNxxxAOEs",
+    "xsxxsxsssxxxx",
+    "nxxxxNxxxAsxx",
+    "nxxxxNxxxAOsx"
+  } ;
+
+  unsigned int stack[n+2] ;
+  unsigned int sp = 0, pos = 0 ;
+  int cont = 1 ;
+
+  stack[0] = n+1 ;
+  tree[n].type = 5 ; /* add ) for the final reduce */
+  tree[n+1].type = 1 ; /* add EOF */
+
+  while (cont)
+  {
+    switch (table[tree[pos].type][tree[stack[sp]].type])
+    {
+      case 'x' : /* error */
+      {
+        char fmt[UINT_FMT] ;
+        fmt[uint_fmt(fmt, pos)] = 0 ;
+        strerr_dief2x(100, "parse error at argument ", fmt) ;
+        break ;
+      }
+      case 'a' : /* accept */
+      {
+        cont = 0 ;
+        break ;
+      }
+      case 's' : /* shift */
+      {
+        stack[++sp] = pos++ ;
+        break ;
+      }
+      case 'n' : /* reduce -> expr without nots, from atom */
+      {
+        switch (tree[stack[sp-1]].type)
+        {
+          case 2 :
+          {
+            tree[stack[sp-1]].arg1 = stack[sp] ;
+            sp-- ;
+            break ;
+          }
+          case 3 :
+          {
+            tree[stack[sp-1]].arg1 = stack[sp-2] ;
+            tree[stack[sp-1]].arg2 = stack[sp] ;
+            stack[sp-2] = stack[sp-1] ;
+            sp -= 2 ;
+            break ;
+          }
+          /* default : assert: its a zero */
+        }
+        tree[stack[sp]].type = 9 ;
+        while (tree[stack[sp-1]].type == 6)
+        {
+          tree[stack[sp-1]].type = 9 ;
+          tree[stack[sp-1]].arg1 = stack[sp] ;
+          sp-- ;
+        }
+        break ;
+      }
+      case 'N' : /* reduce -> expr without nots, from expr */
+      {
+        if (tree[stack[sp-2]].type != 4)
+        {
+          char fmt[UINT_FMT] ;
+          fmt[uint_fmt(fmt, pos)] = 0 ;
+          strerr_dief2x(100, "parse error: bad right parenthesis at argument ", fmt) ;
+        }
+        stack[sp-2] = stack[sp-1] ;
+        sp -= 2 ;
+        tree[stack[sp]].type = 9 ;
+        while (tree[stack[sp-1]].type == 6)
+        {
+          tree[stack[sp-1]].type = 9 ;
+          tree[stack[sp-1]].arg1 = stack[sp] ;
+          sp-- ;
+        }
+        break ;
+      }
+      case 'A' : /* reduce -> exprs without ands */
+      {
+        if (tree[stack[sp-1]].type == 7)
+        {
+          tree[stack[sp-1]].arg1 = stack[sp-2] ;
+          tree[stack[sp-1]].arg2 = stack[sp] ;
+          stack[sp-2] = stack[sp-1] ;
+          sp -= 2 ;
+        }
+        tree[stack[sp]].type = 10 ;
+        break ;
+      }
+      case 'O' : /* reduce -> expr without ors */
+      {
+        if (tree[stack[sp-1]].type == 8)
+        {
+          tree[stack[sp-1]].arg1 = stack[sp-2] ;
+          tree[stack[sp-1]].arg2 = stack[sp] ;
+          stack[sp-2] = stack[sp-1] ;
+          sp -= 2 ;
+        }
+        tree[stack[sp]].type = 11 ;
+        break ;
+      }
+      case 'E' : /* reduce -> expr */
+      {
+        tree[stack[sp]].type = 12 ;
+        break ;
+      }
+      default : /* can't happen */
+        strerr_dief1x(101, "internal error, please submit a bug-report.") ;
+    }
+  }
+  if (sp != 2) strerr_dief1x(100, "parse error: too many left parentheses") ;
+  return stack[1] ;
+}
+
+static int run (struct node const *tree, unsigned int root)
+{
+  switch (tree[root].op)
+  {
+    case T_NOT :
+      return !run(tree, tree[root].arg1) ;
+    case T_AND :
+      return run(tree, tree[root].arg1) && run(tree, tree[root].arg2) ;
+    case T_OR :
+      return run(tree, tree[root].arg1) || run(tree, tree[root].arg2) ;
+    case T_EXIST :
+    {
+      struct stat st ;
+      return !stat(tree[tree[root].arg1].data, &st) ;
+    }
+    case T_BLOCK :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return S_ISBLK(st.st_mode) ;
+    }
+    case T_CHAR :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return S_ISCHR(st.st_mode) ;
+    }
+    case T_DIR :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return S_ISDIR(st.st_mode) ;
+    }
+    case T_REGULAR :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return S_ISREG(st.st_mode) ;
+    }
+    case T_FIFO :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return S_ISFIFO(st.st_mode) ;
+    }
+    case T_SOCKET :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return S_ISSOCK(st.st_mode) ;
+    }
+    case T_SYMLINK :
+    {
+      struct stat st ;
+      if (lstat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return S_ISLNK(st.st_mode) ;
+    }
+    case T_SGID :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return (st.st_mode & S_ISGID) ;
+    }
+    case T_SUID :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return (st.st_mode & S_ISUID) ;
+    }
+    case T_STICKY :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return (st.st_mode & S_ISVTX) ;
+    }
+    case T_NONZEROFILE :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return (st.st_size > 0) ;
+    }
+    case T_MODIFIED :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return (st.st_mtime > st.st_atime) ;
+    }
+    case T_EUID :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return st.st_uid == geteuid() ;
+    }
+    case T_EGID :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      return st.st_gid == getegid() ;
+    }
+    case T_READABLE :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      if (st.st_uid == geteuid()) return st.st_mode & S_IRUSR ;
+      else if (st.st_gid == getegid()) return st.st_mode & S_IRGRP ;
+      else return st.st_mode & S_IROTH ;
+    }
+    case T_WRITABLE :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      if (st.st_uid == geteuid()) return st.st_mode & S_IWUSR ;
+      else if (st.st_gid == getegid()) return st.st_mode & S_IWGRP ;
+      else return st.st_mode & S_IWOTH ;
+    }
+    case T_EXECUTABLE :
+    {
+      struct stat st ;
+      if (stat(tree[tree[root].arg1].data, &st) == -1) return 0 ;
+      if (st.st_uid == geteuid()) return st.st_mode & S_IXUSR ;
+      else if (st.st_gid == getegid()) return st.st_mode & S_IXGRP ;
+      else return st.st_mode & S_IXOTH ;
+    }
+    case T_NEWER :
+    {
+      struct stat st1, st2 ;
+      if (stat(tree[tree[root].arg1].data, &st1) == -1) return 0 ;
+      if (stat(tree[tree[root].arg2].data, &st2) == -1) return 1 ;
+      return st1.st_mtime > st2.st_mtime ;
+    }
+    case T_OLDER :
+    {
+      struct stat st1, st2 ;
+      if (stat(tree[tree[root].arg1].data, &st1) == -1) return 1 ;
+      if (stat(tree[tree[root].arg2].data, &st2) == -1) return 0 ;
+      return st1.st_mtime < st2.st_mtime ;
+    }
+    case T_DEVINO :
+    {
+      struct stat st1, st2 ;
+      if (stat(tree[tree[root].arg1].data, &st1) == -1) return 0 ;
+      if (stat(tree[tree[root].arg2].data, &st2) == -1) return 1 ;
+      return (st1.st_dev == st2.st_dev) && (st1.st_ino == st2.st_ino) ;
+    }
+    case T_TERM :
+    {
+      unsigned int fd ;
+      if (!uint0_scan(tree[tree[root].arg1].data, &fd))
+        strerr_dief2x(100, tree[root].data, " requires an integer argument") ;
+      return isatty((int)fd) ;
+    }
+    case T_NONZERO :
+      return tree[tree[root].arg1].data[0] ;
+    case T_ZERO :
+      return !tree[tree[root].arg1].data[0] ;
+    case T_STREQUAL :
+      return !str_diff(tree[tree[root].arg1].data, tree[tree[root].arg2].data) ;
+    case T_STRNEQUAL :
+      return !!str_diff(tree[tree[root].arg1].data, tree[tree[root].arg2].data) ;
+    case T_STRLESSER :
+      return str_diff(tree[tree[root].arg1].data, tree[tree[root].arg2].data) < 0 ;
+    case T_STRLESSERE :
+      return str_diff(tree[tree[root].arg1].data, tree[tree[root].arg2].data) <= 0 ;
+    case T_STRGREATER :
+      return str_diff(tree[tree[root].arg1].data, tree[tree[root].arg2].data) > 0 ;
+    case T_STRGREATERE :
+      return str_diff(tree[tree[root].arg1].data, tree[tree[root].arg2].data) >= 0 ;
+    case T_NUMEQUAL :
+    {
+      int n1, n2 ;
+      if (!int_scan(tree[tree[root].arg1].data, &n1)
+       || !int_scan(tree[tree[root].arg2].data, &n2))
+        goto errorint ;
+      return n1 == n2 ;
+    }
+    case T_NUMNEQUAL :
+    {
+      int n1, n2 ;
+      if (!int_scan(tree[tree[root].arg1].data, &n1)
+       || !int_scan(tree[tree[root].arg2].data, &n2))
+        goto errorint ;
+      return n1 != n2 ;
+    }
+    case T_NUMGREATER :
+    {
+      int n1, n2 ;
+      if (!int_scan(tree[tree[root].arg1].data, &n1)
+       || !int_scan(tree[tree[root].arg2].data, &n2))
+        goto errorint ;
+      return n1 > n2 ;
+    }
+    case T_NUMGREATERE :
+    {
+      int n1, n2 ;
+      if (!int_scan(tree[tree[root].arg1].data, &n1)
+       || !int_scan(tree[tree[root].arg2].data, &n2))
+        goto errorint ;
+      return n1 >= n2 ;
+    }
+    case T_NUMLESSER :
+    {
+      int n1, n2 ;
+      if (!int_scan(tree[tree[root].arg1].data, &n1)
+       || !int_scan(tree[tree[root].arg2].data, &n2))
+        goto errorint ;
+      return n1 < n2 ;
+    }
+    case T_NUMLESSERE :
+    {
+      int n1, n2 ;
+      if (!int_scan(tree[tree[root].arg1].data, &n1)
+       || !int_scan(tree[tree[root].arg2].data, &n2))
+        goto errorint ;
+      return n1 <= n2 ;
+    }
+    default:
+      strerr_dief1x(111, "operation not implemented") ;
+  }
+
+errorint:
+  strerr_dief2x(100, tree[root].data, " requires integer arguments") ;
+}
+
+int main (int argc, char const *const *argv)
+{
+  PROG = "s6-test" ;
+  if (argc <= 1) return 1 ;
+  {
+    struct node tree[argc + 2] ;    
+    unsigned int n = lex(tree, argv+1) ;
+    if ((argv[0][0] == '[') && !argv[0][1])
+    {
+      if (n && (!tree[n-1].type) && (tree[n-1].data[0] == ']') && !tree[n-1].data[1])
+        n-- ;
+      else strerr_dief1x(100, "parse error: missing closing bracket") ;
+    }
+    return !run(tree, parse(tree, n)) ;
+  }
+}