Applied debian patch to fix compiler warnings.

0014-fix-implicit-declarations-incompatible-types-argv-ty.patch

From: Jan <cloux@rote.ch>
Date: Sat, 2 Mar 2019 15:41:59 +0100
Subject: fix: implicit declarations, incompatible types, argv type
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Fixed a few compiler warnings:

prot.c:13:7: warning: implicit declaration of function ‘setgroups’ [-Wimplicit-function-declaration]
chpst.c:80:7: warning: implicit declaration of function ‘setgroups’; did you mean ‘getgroups’? [-Wimplicit-function-declaration]
 - added #include <grp.h>, see: https://linux.die.net/man/2/setgroups

chkshsgr.c:11:19: warning: passing argument 2 of ‘getgroups’ from incompatible pointer type [-Wincompatible-pointer-types]
 - change 'short' to 'gid_t', see: https://linux.die.net/man/2/setgroups

pathexec_run.c:18:5: warning: implicit declaration of function ‘execve’ [-Wimplicit-function-declaration]
 - add #include <unistd.h>, see: http://man7.org/linux/man-pages/man2/execve.2.html

prot.c:17:10: warning: implicit declaration of function ‘setgid’; did you mean ‘getgrgid’? [-Wimplicit-function-declaration]
 - add #include <unistd.h>, see: https://linux.die.net/man/3/setgid

seek_set.c:9:7: warning: implicit declaration of function ‘lseek’ [-Wimplicit-function-declaration]
 - add #include <unistd.h>, see: https://linux.die.net/man/2/lseek

--------------------------------------

Fixed type of argv, from 'const char **argv' to 'char **argv'
This resolves a lot of compiler typecast warnings like:
pathexec_run.c:19:17: warning: passing argument 2 of ‘execve’ from incompatible pointer type [-Wincompatible-pointer-types]

NOTE: this change might be disputable and not obvious at first.
For arguments for argv as 'char **argv', see:

The C Programming Language, Kernighan & Ritchie, Second Edition,  Section 5.10, page 110
Command-line Arguments:  main(int argc, char *argv[])

From https://riptutorial.com/c/example/3675/original--hello--world---in-k-r-c
int main(int argc, char **argv)

From C/C++ Kompendium (DE), Markt+Technik Verlag 2000, page 576, Chapter 12, main() Parameter:
int main(int argc, char *argv[])

From http://www.cplusplus.com/articles/DEN36Up4/
int main(int argc, char* argv[]) // or char** argv

From https://ece.uwaterloo.ca/~dwharder/icsrts/C/05/
int main( int argc, char *argv[] )

At
https://stackoverflow.com/questions/5808679/why-is-main-argument-argv-of-type-char-rather-than-const-char
is argued, that:
 - argv isn't const, since it's being created at runtime
 - in certain cases you should be able to rewrite argv from you program

The main argument for this type change:
the argv is used in a call to execve, so the type should be declared as compatible
with execve parameters.  http://man7.org/linux/man-pages/man2/execve.2.html
defines:
int execve(const char *filename, char *const argv[], char *const envp[]);

so every argv defined as 'const char *const argv[]' was changed to:
'char *const argv[]'

1 files changed, 4 insertions, 4 deletions

diff --git a/pathexec_env.c b/pathexec_env.c
index 1305469..f873094 100644
--- a/pathexec_env.c
+++ b/pathexec_env.c
@@ -22,9 +22,9 @@ int pathexec_env(const char *s,const char *t)
   return stralloc_cat(&plus,&tmp);
 }
 
-void pathexec_env_run(const char *file, const char *const *argv)
+void pathexec_env_run(const char *file, char *const *argv)
 {
-  const char **e;
+  char **e;
   unsigned int elen;
   unsigned int i;
   unsigned int j;
@@ -40,7 +40,7 @@ void pathexec_env_run(const char *file, const char *const *argv)
     if (!plus.s[i])
       ++elen;
 
-  e = (const char **) alloc((elen + 1) * sizeof(char *));
+  e = (char **) alloc((elen + 1) * sizeof(char *));
   if (!e) return;
 
   elen = 0;
@@ -68,7 +68,7 @@ void pathexec_env_run(const char *file, const char *const *argv)
   alloc_free(e);
 }
 
-void pathexec(const char *const *argv)
+void pathexec(char *const *argv)
 {
   return pathexec_env_run(*argv, argv);
 }