Add path_canonicalize, prepare for 2.9.1.0

8 files changed, 99 insertions, 2 deletions

diff --git a/NEWS b/NEWS
index 27b7eae..8ed0191 100644
--- a/NEWS
+++ b/NEWS
@@ -1,5 +1,11 @@
 Changelog for skalibs.
 
+In 2.9.1.0
+----------
+
+ - Added path_canonicalize()
+
+
 In 2.9.0.0
 ----------
 
diff --git a/doc/index.html b/doc/index.html
index 18fa214..8a903f1 100644
--- a/doc/index.html
+++ b/doc/index.html
@@ -60,7 +60,7 @@ with a standard C development environment </li>
 <h3> Download </h3>
 
 <ul>
- <li> The current released version of skalibs is <a href="skalibs-2.9.0.0.tar.gz">2.9.0.0</a>. </li>
+ <li> The current released version of skalibs is <a href="skalibs-2.9.1.0.tar.gz">2.9.1.0</a>. </li>
  <li> Alternatively, you can checkout a copy of the
 <a href="//git.skarnet.org/cgi-bin/cgit.cgi/skalibs/">skalibs
 git repository</a>:
diff --git a/doc/libstddjb/djbunix.html b/doc/libstddjb/djbunix.html
index dca3a2c..6223bf4 100644
--- a/doc/libstddjb/djbunix.html
+++ b/doc/libstddjb/djbunix.html
@@ -808,5 +808,18 @@ Sleeps <em>n</em> milliseconds. Signals received during that time are handled,
 but <em>do not</em> interrupt the sleep.
 </p>
 
+<h3> Miscellaneous functions </h3>
+
+<p>
+<code> size_t path_canonicalize (char *out, char const *in, int check) </code> <br />
+Writes into <em>out</em> the canonical form of the Unix path given in
+<em>in</em>. The <em>out</em> array must be preallocated with at least
+<tt>strlen(in)+2</tt> bytes. Returns the length of the <em>out</em> path, without
+counting the terminating null byte. If <em>check</em> is nonzero, <em>in</em> is tested
+for every <tt>foobar/..</tt> element, and the function returns 0, and sets errno
+appropriately, if <tt>foobar</tt> is not a valid directory; in that case, <em>out</em>
+contains the problematic path.
+</p>
+
 </body>
 </html>
diff --git a/doc/upgrade.html b/doc/upgrade.html
index b5f7031..314a3ce 100644
--- a/doc/upgrade.html
+++ b/doc/upgrade.html
@@ -16,6 +16,12 @@
 <a href="//skarnet.org/">skarnet.org</a>
 </p>
 
+<h2> in 2.9.1.0 </h2>
+
+<ul>
+ <li> New function: <tt>path_canonicalize</tt> </li>
+</ul>
+
 <h2> in 2.9.0.0 </h2>
 
 <ul>
diff --git a/package/deps.mak b/package/deps.mak
index 5970bb9..77008c8 100644
--- a/package/deps.mak
+++ b/package/deps.mak
@@ -458,6 +458,7 @@ src/libstddjb/openwritenclose_unsafe.o src/libstddjb/openwritenclose_unsafe.lo:
 src/libstddjb/openwritevnclose.o src/libstddjb/openwritevnclose.lo: src/libstddjb/openwritevnclose.c src/include/skalibs/djbunix.h
 src/libstddjb/openwritevnclose_suffix.o src/libstddjb/openwritevnclose_suffix.lo: src/libstddjb/openwritevnclose_suffix.c src/include/skalibs/djbunix.h
 src/libstddjb/openwritevnclose_unsafe.o src/libstddjb/openwritevnclose_unsafe.lo: src/libstddjb/openwritevnclose_unsafe.c src/include/skalibs/allreadwrite.h src/include/skalibs/djbunix.h
+src/libstddjb/path_canonicalize.o src/libstddjb/path_canonicalize.lo: src/libstddjb/path_canonicalize.c src/include/skalibs/djbunix.h
 src/libstddjb/pathexec.o src/libstddjb/pathexec.lo: src/libstddjb/pathexec.c src/include/skalibs/djbunix.h src/include/skalibs/env.h src/include/skalibs/posixplz.h
 src/libstddjb/pathexec0.o src/libstddjb/pathexec0.lo: src/libstddjb/pathexec0.c src/include/skalibs/djbunix.h
 src/libstddjb/pathexec0_run.o src/libstddjb/pathexec0_run.lo: src/libstddjb/pathexec0_run.c src/include/skalibs/djbunix.h
diff --git a/package/info b/package/info
index ab9f643..403794d 100644
--- a/package/info
+++ b/package/info
@@ -1,4 +1,4 @@
 package=skalibs
-version=2.9.0.0
+version=2.9.1.0
 category=prog
 package_macro_name=SKALIBS
diff --git a/src/include/skalibs/djbunix.h b/src/include/skalibs/djbunix.h
index d39df3f..fe8c2f9 100644
--- a/src/include/skalibs/djbunix.h
+++ b/src/include/skalibs/djbunix.h
@@ -53,6 +53,8 @@ extern int open_write (char const *) ;
 extern int socket_internal (int, int, int, unsigned int) ;
 extern int socketpair_internal (int, int, int, unsigned int, int *) ;
 
+extern size_t path_canonicalize (char *, char const *, int) ;
+
 extern int pathexec_env (char const *, char const *) ;
 extern void pathexec_r (char const *const *, char const *const *, size_t, char const *, size_t) ;
 extern void pathexec_r_name (char const *, char const *const *, char const *const *, size_t, char const *, size_t) ;
diff --git a/src/libstddjb/path_canonicalize.c b/src/libstddjb/path_canonicalize.c
new file mode 100644
index 0000000..c30f9f4
--- /dev/null
+++ b/src/libstddjb/path_canonicalize.c
@@ -0,0 +1,69 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <sys/stat.h>
+
+#include <skalibs/djbunix.h>
+
+static unsigned char cclass (char c)
+{
+  switch (c)
+  {
+    case 0 : return 0 ;
+    case '/' : return 1 ;
+    case '.' : return 2 ;
+    default : return 3 ;
+  }
+}
+
+ /* out must be at least strlen(in) + 2 bytes */
+
+size_t path_canonicalize (char *out, char const *in, int check)
+{
+  static unsigned char const table[4][4] =
+  {
+    { 0x04, 0x00, 0x12, 0x11 },
+    { 0x04, 0x50, 0x11, 0x11 },
+    { 0x24, 0x20, 0x13, 0x11 },
+    { 0xa4, 0xa0, 0x11, 0x11 }
+  } ;
+  int isabsolute = in[0] == '/' ;
+  size_t j = 0 ;
+  unsigned int depth = 0 ;
+  unsigned char state = 0 ;
+
+  if (isabsolute) *out++ = *in++ ;
+  while (state < 4)
+  {
+    char c = *in++ ;
+    unsigned char what = table[state][cclass(c)] ;
+    state = what & 0x07 ;
+    if (what & 0x80)
+    {
+      if (depth)
+      {
+        depth-- ;
+        j -= 3 ;
+        if (check)
+        {
+          struct stat st ;
+          out[j] = 0 ;
+          if (stat(out - isabsolute, &st) < 0) return 0 ;
+          if (!S_ISDIR(st.st_mode)) return (errno = ENOTDIR, 0) ;
+        }
+      }
+      else if (!isabsolute)
+      {
+        out[j++] = '/' ;
+        out[j++] = '.' ;
+      }
+    }
+    if (what & 0x40) depth++ ;
+    if (what & 0x20) while (j && out[j-1] != '/') j-- ;
+    if (what & 0x10) out[j++] = c ;
+  }
+  if (j && out[j-1] == '/') j-- ;
+  if (!j && !isabsolute) out[j++] = '.' ;
+  out[j] = 0 ;
+  return j ;
+}