From fd5cdae359835518d9f9d3186340f73813e70a76 Mon Sep 17 00:00:00 2001
From: Benxi Liu <bxliu@linux.alibaba.com>
Date: Thu, 1 Aug 2019 09:52:40 +0800
Subject: [PATCH] mraa: fix mraa_file_contains() and mraa_file_contains_both()

These two functions may return wrong results if lines in the
file contains embedded '\0' characters.

For example, file "/proc/device-tree/compatible" could have
multiple values in one line (corresponding to the dts), and the
values are separated with '\0'.

In this situation, we need to replace the embedded '\0' and check
the entire line. If we don't do this, only the first value is
checked by strstr(), and the function may return false even if
the file contains certain content.

Signed-off-by: Benxi Liu <bxliu@linux.alibaba.com>
---
 src/mraa.c | 24 ++++++++++++++++++++++--
 1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/src/mraa.c b/src/mraa.c
index 039d96a36..eab95a7c7 100644
--- a/src/mraa.c
+++ b/src/mraa.c
@@ -1068,13 +1068,23 @@ mraa_file_contains(const char* filename, const char* content)
     char* file = mraa_file_unglob(filename);
     if (file != NULL) {
         size_t len = 0;
+        size_t read = 0;
         char* line = NULL;
         FILE* fh = fopen(file, "r");
         if (fh == NULL) {
             free(file);
             return 0;
         }
-        while ((getline(&line, &len, fh) != -1) && (found == 0)) {
+        while (((read = getline(&line, &len, fh)) != -1) && (found == 0)) {
+            if (strlen(line) < read) {
+                char* ptr = line;
+                while (ptr < line + read) {
+                    if (*ptr == '\0') {
+                        *ptr = ' ';
+                    }
+                    ++ptr;
+                }
+            }
             if (strstr(line, content)) {
                 found = 1;
                 break;
@@ -1098,13 +1108,23 @@ mraa_file_contains_both(const char* filename, const char* content, const char* c
     char* file = mraa_file_unglob(filename);
     if (file != NULL) {
         size_t len = 0;
+        size_t read = 0;
         char* line = NULL;
         FILE* fh = fopen(file, "r");
         if (fh == NULL) {
             free(file);
             return 0;
         }
-        while ((getline(&line, &len, fh) != -1) && (found == 0)) {
+        while (((read = getline(&line, &len, fh)) != -1) && (found == 0)) {
+            if (strlen(line) < read) {
+                char* ptr = line;
+                while (ptr < line + read) {
+                    if (*ptr == '\0') {
+                        *ptr = ' ';
+                    }
+                    ++ptr;
+                }
+            }
             if (strstr(line, content) && strstr(line, content2)) {
                 found = 1;
                 break;