Initial commit.

3 files changed, 325 insertions, 0 deletions

diff --git a/src/config/deps-exe/s6-frontend-config-preprocess b/src/config/deps-exe/s6-frontend-config-preprocess
new file mode 100644
index 0000000..e7187fe
--- /dev/null
+++ b/src/config/deps-exe/s6-frontend-config-preprocess
@@ -0,0 +1 @@
+-lskarnet
diff --git a/src/config/s6-frontend-config-preprocess.c b/src/config/s6-frontend-config-preprocess.c
new file mode 100644
index 0000000..db09e24
--- /dev/null
+++ b/src/config/s6-frontend-config-preprocess.c
@@ -0,0 +1,286 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+#include <skalibs/uint64.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/buffer.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/direntry.h>
+#include <skalibs/djbunix.h>
+#include <skalibs/skamisc.h>
+#include <skalibs/avltree.h>
+
+#define USAGE "s6-frontend-config-preprocess file"
+#define dieusage() strerr_dieusage(100, USAGE)
+#define dienomem() strerr_diefu1sys(111, "stralloc_catb") ;
+#define MAXDEPTH 100
+
+static stralloc sa = STRALLOC_ZERO ;
+static unsigned int depth = 0 ;
+
+
+ /* Name storage */
+
+static stralloc namesa = STRALLOC_ZERO ;
+
+static void *name_dtok (uint32_t pos, void *aux)
+{
+  (void)aux ;
+  return namesa.s + pos ;
+}
+
+static int name_cmp (void const *a, void const *b, void *aux)
+{
+  (void)aux ;
+  return strcmp((char const *)a, (char const *)b) ;
+}
+
+static avltree namemap = AVLTREE_INIT(8, 3, 8, &name_dtok, &name_cmp, 0) ;
+
+
+ /* Directory sorting */
+
+static char *dname_cmp_base ;
+static int dname_cmp (void const *a, void const *b)
+{
+  return strcmp(dname_cmp_base + *(size_t *)a, dname_cmp_base + *(size_t *)b) ;
+}
+
+
+ /* Recursive inclusion functions */
+
+static int includefromhere (char const *, int) ;
+
+static inline void includecwd (int once)
+{
+  genalloc ga = GENALLOC_ZERO ; /* size_t */
+  DIR *dir ;
+  size_t sabase = sa.len ;
+  if (sagetcwd(&sa) < 0 || !stralloc_0(&sa)) dienomem() ;
+  dir = opendir(".") ;
+  if (!dir) strerr_diefu2sys(111, "opendir ", sa.s + sabase) ;
+
+  for (;;)
+  {
+    direntry *d ;
+    errno = 0 ;
+    d = readdir(dir) ;
+    if (!d) break ;
+    if (d->d_name[0] == '.') continue ;
+    if (!genalloc_catb(size_t, &ga, &sa.len, 1)) break ;
+    if (!stralloc_catb(&sa, d->d_name, strlen(d->d_name)+1)) break ;
+  }
+  dir_close(dir) ;
+  if (errno) strerr_diefu2sys(111, "readdir ", sa.s + sabase) ;
+
+  dname_cmp_base = sa.s ;
+  qsort(genalloc_s(size_t, &ga), genalloc_len(size_t, &ga), sizeof(size_t), &dname_cmp) ;
+
+  for (size_t i = 0 ; i < genalloc_len(size_t, &ga) ; i++)
+    if (!includefromhere(sa.s + genalloc_s(size_t, &ga)[i], once))
+      strerr_dief4sys(1, "in ", sa.s + sabase, ": unable to include ", sa.s + genalloc_s(size_t, &ga)[i]) ;
+
+  genalloc_free(size_t, &ga) ;
+  sa.len = sabase ;
+}
+
+static int include (char const *file, int once)
+{
+  size_t sabase = sa.len ;
+  size_t filelen = strlen(file) ;
+  if (!sadirname(&sa, file, filelen) || !stralloc_0(&sa)) dienomem() ;
+  if (chdir(sa.s + sabase) < 0) return 0 ;
+  sa.len = sabase ;
+  if (!sabasename(&sa, file, filelen)) dienomem() ;
+  {
+    char fn[sa.len + 1 - sabase] ;
+    memcpy(fn, sa.s + sabase, sa.len - sabase) ;
+    fn[sa.len - sabase] = 0 ;
+    sa.len = sabase ;
+    return includefromhere(fn, once) ;
+  }
+}
+
+static inline int idcmd (char const *s)
+{
+  static char const *commands[] =
+  {
+    "include",
+    "includeonce",
+    "includedir",
+    "includedironce",
+    0
+  } ;
+  for (char const **p = commands ; *p ; p++)
+    if (!strcmp(s, *p)) return p - commands ;
+  return -1 ;
+}
+
+static inline unsigned char cclass (char c)
+{
+  static unsigned char const classtable[34] = "0444444443144344444444444444444432" ;
+  return (unsigned char)c < 34 ? classtable[(unsigned char)c] - '0' : 4 ;
+}
+
+static int includefromhere (char const *file, int once)
+{
+  size_t sabase = sa.len ;
+  if (sarealpath(&sa, file) < 0 || !stralloc_0(&sa)) return 0 ;
+
+  if (once)
+  {
+    uint32_t dummy ;
+    if (avltree_search(&namemap, sa.s + sabase, &dummy)) goto end ;
+    {
+      size_t cur = namesa.len ;
+      size_t filelen = strlen(file) ;
+      if (cur + filelen + 2 < cur || cur + filelen + 2 > UINT32_MAX)
+        strerr_dief3x(3, "in ", sa.s + sabase, ": too much nesting") ;
+      if (!stralloc_catb(&namesa, sa.s + sabase, sa.len - sabase)) dienomem() ;
+      if (!avltree_insert(&namemap, cur)) dienomem() ;
+    }
+  }
+
+  if (depth++ > MAXDEPTH)
+    strerr_dief3x(3, "in ", sa.s + sabase, ": too much nesting") ;
+
+  {
+    static unsigned char const table[8][5] =
+    {
+      { 0x08, 0x10, 0x02, 0x10, 0x10 },
+      { 0x08, 0x10, 0x11, 0x11, 0x11 },
+      { 0x08, 0x00, 0x03, 0x04, 0x25 },
+      { 0x08, 0x00, 0x03, 0x03, 0x03 },
+      { 0x09, 0x09, 0x09, 0x04, 0x25 },
+      { 0x09, 0x09, 0x09, 0x46, 0x25 },
+      { 0x0a, 0x0a, 0x07, 0x06, 0x27 },
+      { 0x88, 0x80, 0x27, 0x27, 0x27 }
+    } ;
+    stralloc localsa = STRALLOC_ZERO ;
+    uint64_t line = 1 ;
+    size_t sacur = sa.len ;
+    int cmd = -1 ;
+    buffer b ;
+    char buf[4096] ;
+    unsigned char state = 0 ;
+    int fd = open_readb(file) ;
+    if (fd < 0) strerr_diefu2sys(111, "open ", sa.s + sabase) ;
+    buffer_init(&b, &buffer_read, fd, buf, 4096) ;
+
+    if (buffer_put(buffer_1, "! 0 ", 4) < 4
+     || buffer_put(buffer_1, sa.s + sabase, sacur - 1 - sabase) < sacur - 1 - sabase
+     || buffer_put(buffer_1, "\n", 1) < 1)
+      strerr_diefu1sys(111, "write to stdout") ;
+
+    while (state < 8)
+    {
+      uint16_t what ;
+      char c = 0 ;
+      if (buffer_get(&b, &c, 1) < 0)
+        strerr_diefu2sys(111, "read from ", sa.s + sabase) ;
+      what = table[state][cclass((unsigned char)c)] ;
+      state = what & 0x000f ;
+      if (what & 0x0010)
+        if (buffer_put(buffer_1, &c, 1) < 1)
+          strerr_diefu1sys(111, "write to stdout") ;
+      if (what & 0x0020)
+        if (!stralloc_catb(&localsa, &c, 1)) dienomem() ;
+      if (what & 0x0040)
+      {
+        if (!stralloc_0(&localsa)) dienomem() ;
+        cmd = idcmd(localsa.s) ;
+        if (cmd < 0)
+        {
+          char fmt[UINT64_FMT] ;
+          fmt[uint64_fmt(fmt, line)] = 0 ;
+          strerr_dief6x(2, "in ", sa.s + sabase, " line ", fmt, ": unrecognized directive: ", localsa.s) ;
+        }
+        localsa.len = 0 ;
+      }
+      if (what & 0x0080)
+      {
+        int fdhere = open(".", O_RDONLY | O_DIRECTORY) ;
+        if (fdhere < 0)
+          strerr_dief3sys(111, "in ", sa.s + sabase, ": unable to open base directory: ") ;
+        if (!stralloc_0(&localsa)) dienomem() ;
+        if (cmd & 2)
+        {
+          if (chdir(localsa.s) < 0)
+          {
+            char fmt[UINT64_FMT] ;
+            fmt[uint64_fmt(fmt, line)] = 0 ;
+            strerr_dief6sys(111, "in ", sa.s + sabase, " line ", fmt, ": unable to chdir to ", localsa.s) ;
+          }
+          includecwd(cmd & 1) ;
+        }
+        else if (!include(localsa.s, cmd & 1))
+        {
+          char fmt[UINT64_FMT] ;
+          fmt[uint64_fmt(fmt, line)] = 0 ;
+          strerr_dief6sys(111, "in ", sa.s + sabase, " line ", fmt, ": unable to include ", localsa.s) ;
+        }
+        if (fchdir(fdhere) < 0)
+          strerr_dief3sys(111, "in ", sa.s + sabase, ": unable to fchdir back") ;
+        fd_close(fdhere) ;
+        localsa.len = 0 ;
+        {
+          char fmt[UINT64_FMT] ;
+          size_t fmtlen = uint64_fmt(fmt, line) ;
+          fmt[fmtlen++] = ' ' ;
+          if (buffer_put(buffer_1, "! ", 2) < 2
+           || buffer_put(buffer_1, fmt, fmtlen) < fmtlen
+           || buffer_put(buffer_1, sa.s + sabase, sacur - 1 - sabase) < sacur - 1 - sabase
+           || buffer_put(buffer_1, "\n", 1) < 1)
+            strerr_diefu1sys(111, "write to stdout") ;
+        }
+      }
+      if (c == '\n' && state <= 8) line++ ;
+    }
+    if (state > 8)
+    {
+      char fmt[UINT64_FMT] ;
+      fmt[uint64_fmt(fmt, line)] = 0 ;
+      strerr_dief5x(2, "in ", sa.s + sabase, " line ", fmt, ": syntax error: invalid ! line") ;
+    }
+    fd_close(fd) ;
+    stralloc_free(&localsa) ;
+  }
+
+ depth-- ;
+ end:
+  sa.len = sabase ;
+  return 1 ;
+}
+
+int main (int argc, char const *const *argv, char const *const *envp)
+{
+  PROG = "s6-frontend-config-preprocess" ;
+  {
+    subgetopt_t l = SUBGETOPT_ZERO ;
+    for (;;)
+    {
+      int opt = subgetopt_r(argc, argv, "", &l) ;
+      if (opt == -1) break ;
+      switch (opt)
+      {
+        default : dieusage() ;
+      }
+    }
+    argc -= l.ind ; argv += l.ind ;
+  }
+  if (!argc) dieusage() ;
+
+  if (!include(argv[0], 1)) strerr_diefu2sys(1, "preprocess ", argv[0]) ;
+  if (!buffer_flush(buffer_1))
+    strerr_diefu1sys(111, "write to stdout") ;
+  return 0 ;
+}
diff --git a/src/config/s6-frontend-config-preprocess.txt b/src/config/s6-frontend-config-preprocess.txt
new file mode 100644
index 0000000..e81c86e
--- /dev/null
+++ b/src/config/s6-frontend-config-preprocess.txt
@@ -0,0 +1,38 @@
+
+ Automaton for the preprocessor:
+
+
+class	|	0	1	2	3	4
+st\ev	|	\0	\n	!	space	other
+
+START	|		print		print	print
+0	|	END	START	CMD	NORMAL	NORMAL
+
+NORMAL	|		print	print	print	print
+1	|	END	START	NORMAL	NORMAL	NORMAL
+
+CMD	|					add
+2	|	END	START	IGNORE	CMD1	CMD2
+
+IGNORE	|
+3	|	END	START	IGNORE	IGNORE	IGNORE
+
+CMD1	|					add
+4	|	X	X	X	CMD1	CMD2
+
+CMD2	|				idcmd   add
+5	|	X	X	X	ARG	CMD2
+
+ARG	|					add
+6	|	X	X	ARG1	ARG	ARG1
+
+ARG1	|	proc	proc    add     add     add
+7	|	END	START	ARG1	ARG1	ARG1
+
+states: 0-7 plus END and X -> 4 bits
+actions: 4. -> 8 bits total, fits in a char.
+
+print 0x10 copies the character to stdout
+add   0x20 adds the character to the processing string
+idcmd 0x40 ids the processing string for an !include cmd
+proc  0x80 gets the filename and procs the include