[PATCH] gnu: Add fontconfig-path-max.

[rennes]

Hello Guix team,

i'm doing tests whith GNU Guix on GNU Hurd, compiling fontconfig and 
there is an error during compilation:

a) fontconfig uses the constant PATH_MAX.

Reviewing the documentation about the treatment of constant for Hurd; 
i've attached a patch for review.

References:
https://www.gnu.org/software/hurd/community/gsoc/project_ideas/maxpath.html
https://www.gnu.org/software/hurd/hurd/porting/guidelines.html

and i've a couple of questions about:

a) How Guix identify if it is a Linux or Hurd system at compile or 
install the package?.
b) i searches in ML an example, but i not found.



Thanks for your time.

ReneFrom 3195bf1e75493675dc8cbd81a0f83e0b4538263b Mon Sep 17 00:00:00 2001
From: Rene Saavedra <ren...@openmailbox.org>
Date: Sat, 18 Jun 2016 13:37:19 -0500
Subject: [PATCH] gnu: Add fontconfig-path-max.

---
 gnu/packages/fontutils.scm                      |  3 +++
 gnu/packages/patches/fontconfig-fcdefault.patch | 23 +++++++++++++++++++++++
 gnu/packages/patches/fontconfig-fcstat.patch    | 23 +++++++++++++++++++++++
 3 files changed, 49 insertions(+)
 create mode 100644 gnu/packages/patches/fontconfig-fcdefault.patch
 create mode 100644 gnu/packages/patches/fontconfig-fcstat.patch

diff --git a/gnu/packages/fontutils.scm b/gnu/packages/fontutils.scm
index 5f6ff15..2b84523 100644
--- a/gnu/packages/fontutils.scm
+++ b/gnu/packages/fontutils.scm
@@ -231,6 +231,9 @@ fonts to/from the WOFF2 format.")
             (uri (string-append
                    "https://www.freedesktop.org/software/fontconfig/release/fontconfig-";
                    version ".tar.bz2"))
+            (patches (list
+                      (search-patch "fontconfig-fcdefault.patch")
+                      (search-patch "fontconfig-fcstat.patch")))
             (sha256 (base32
                      "1psrl4b4gi4wmbvwwh43lk491wsl8lgvqj146prlcha3vwjc0qyp"))))
    (build-system gnu-build-system)
diff --git a/gnu/packages/patches/fontconfig-fcdefault.patch b/gnu/packages/patches/fontconfig-fcdefault.patch
new file mode 100644
index 0000000..9c3b383
--- /dev/null
+++ b/gnu/packages/patches/fontconfig-fcdefault.patch
@@ -0,0 +1,23 @@
+This patch replaces the use of macro PATH_MAX by *buf constant,
+which allows dynamic memory allocation.
+
+---
+ src/fcdefault.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/fcdefault.c b/src/fcdefault.c
+index 6647a8f..8e2094f 100644
+--- a/src/fcdefault.c
++++ b/src/fcdefault.c
+@@ -150,7 +150,7 @@ retry:
+ # if defined (HAVE_GETEXECNAME)
+ 	const char *p = getexecname ();
+ # elif defined (HAVE_READLINK)
+-	char buf[PATH_MAX + 1];
++	char *buf;
+ 	int len;
+ 	char *p = NULL;
+ 
+-- 
+2.6.3
+
diff --git a/gnu/packages/patches/fontconfig-fcstat.patch b/gnu/packages/patches/fontconfig-fcstat.patch
new file mode 100644
index 0000000..e075b17
--- /dev/null
+++ b/gnu/packages/patches/fontconfig-fcstat.patch
@@ -0,0 +1,23 @@
+This patch replaces the use of macro PATH_MAX by *f constant,
+which allows dynamic memory allocation.
+
+---
+ src/fcstat.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/fcstat.c b/src/fcstat.c
+index 1734fa4..8a438eb 100644
+--- a/src/fcstat.c
++++ b/src/fcstat.c
+@@ -278,7 +278,7 @@ FcDirChecksum (const FcChar8 *dir, time_t *checksum)
+ 	{
+ #endif
+ 	struct stat statb;
+-	char f[PATH_MAX + 1];
++	char *f;
+ 
+ 	memcpy (f, dir, len);
+ 	f[len] = FC_DIR_SEPARATOR;
+-- 
+2.6.3
+
-- 
2.6.3