From b32d266a8c29bfe1d6818c07a9523f0ef2dcf137 Mon Sep 17 00:00:00 2001
From: Stefan Lankes <slankes@eonerc.rwth-aachen.de>
Date: Sun, 9 Oct 2016 08:55:10 +0200
Subject: [PATCH] remove dependency of the PCRE library

---
 .travis.yml           |  2 +-
 README.md             |  2 +-
 hermit/tools/Makefile |  2 +-
 hermit/tools/proxy.c  | 23 +++++++----------------
 4 files changed, 10 insertions(+), 19 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 6ec31d3ea..c73437d10 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,7 +6,7 @@ language: c
 compiler: gcc
 before_install:
         - sudo apt-get -qq update
-        - sudo apt-get install -y curl qemu-system-x86 nasm texinfo libpcre3-dev libmpfr-dev libmpc-dev libgmp-dev libisl-dev flex bison
+        - sudo apt-get install -y curl qemu-system-x86 nasm texinfo libmpfr-dev libmpc-dev libgmp-dev libisl-dev flex bison
         - git submodule update --init hermit/lwip hermit/usr/gcc hermit/usr/pte hermit/usr/libomp
 script:
         - ./configure
diff --git a/README.md b/README.md
index ced0239e1..b4b5e7b86 100644
--- a/README.md
+++ b/README.md
@@ -23,7 +23,7 @@ The build process works currently only on **x86-based Linux** systems. The follo
 
 On Debian-based systems the packets can be installed by executing:
 ```
-  sudo apt-get install qemu-system-x86 nasm texinfo libpcre3-dev libmpfr-dev libmpc-dev libgmp-dev libisl-dev flex bison
+  sudo apt-get install qemu-system-x86 nasm texinfo libmpfr-dev libmpc-dev libgmp-dev libisl-dev flex bison
 ```
 
 ## Building and testing HermitCore as multi-kernel within a virtual machine
diff --git a/hermit/tools/Makefile b/hermit/tools/Makefile
index f8102729d..a9fa8b31d 100644
--- a/hermit/tools/Makefile
+++ b/hermit/tools/Makefile
@@ -19,7 +19,7 @@ all: proxy
 
 proxy: proxy.o
 	@echo [LD] $@
-	$Q$(CC) $(CFLAGS) -o $@ $< -lpcre
+	$Q$(CC) $(CFLAGS) -o $@ $<
 
 clean:
 	@echo Cleaning tools
diff --git a/hermit/tools/proxy.c b/hermit/tools/proxy.c
index 2a9887bb5..936a8e0e9 100644
--- a/hermit/tools/proxy.c
+++ b/hermit/tools/proxy.c
@@ -45,7 +45,6 @@
 #include <sys/wait.h>
 #include <unistd.h>
 #include <stdint.h>
-#include <pcre.h>
 
 #define MAX_PATH	255
 #define MAX_ARGS	1024
@@ -106,36 +105,28 @@ static void exit_handler(int sig)
 
 static char* cpufreq(void)
 {
-	const char* pattern = "^cpu MHz\\s*:\\s*(\\d+)";
-	const char* pcreErrorStr = NULL;
-	int creErrorOffset = 0;
 	char line[2048];
 	const char* match = NULL;
-	int rc, results[10];
-	
-	pcre* reCompiled = pcre_compile(pattern, PCRE_ANCHORED, &pcreErrorStr, &creErrorOffset, NULL);
-
-	if(reCompiled == NULL)
-		return "0";
 
 	FILE* fp = fopen("/proc/cpuinfo", "r");
 	if (!fp)
-		return "0";
+		return "-freq0";
 
 	while(fgets(line, 2048, fp)) {
-		if ((rc = pcre_exec(reCompiled, 0, line, 2048, 0, 0, results, 10)) < 0)
+		if ((match = strstr(line, "cpu MHz")) == NULL)
 			continue;
 
-		pcre_get_substring(line, results, rc, 1, &(match));
+		// scan strinf for the next number
+		for(; (*match < 0x30) || (*match > 0x39); match++)
+			;
+
 		snprintf(cmdline, MAX_PATH, "-freq%s", match);	
 		fclose(fp);
-		pcre_free_substring(match);
-		pcre_free(reCompiled);
 
 		return cmdline;
 	}
 
-	return "0";
+	return "-freq0";
 }
 
 static int init_env(char *path)