add new functions notcurses_{host,account}name()

NEWS.md

@@ -1,7 +1,9 @@
 This document attempts to list user-visible changes and any major internal
 rearrangements of Notcurses.
 
-* 2.3.13 (not yet released)
+* 2.3.13 (2021-08-04)
+  * Added the portable utility functions `notcurses_accountname()` and
+    `notcurses_hostname()`.
 
 * 2.3.12 (2021-07-29)
   * `notcurses_getc()` and `ncdirect_getc()` no longer accept a `sigset_t*`

doc/man/index.html

@@ -76,6 +76,7 @@
    <a href="notcurses_stop.3.html">notcurses_stop</a>—collapse the context<br/>
    <a href="notcurses_tabbed.3.html">notcurses_tabbed</a>—tabbed interface widget<br/>
    <a href="notcurses_tree.3.html">notcurses_tree</a>—line-based widget for hierarchical data<br/>
+   <a href="notcurses_util.3.html">notcurses_util</a>—portable utility functions<br/>
    <a href="notcurses_visual.3.html">notcurses_visual</a>—operations on <tt>ncvisual</tt> objects<br/>
   </div>
   <div style="float:right;clear:right">

doc/man/man3/notcurses_util.3.md

@@ -0,0 +1,35 @@
+% notcurses_util(3)
+% nick black <nickblack@linux.com>
+% v2.3.12
+
+# NAME
+
+notcurses_util - portable utility functions
+
+# SYNOPSIS
+
+**#include <notcurses/notcurses.h>**
+
+**char* notcurses_accountname(void);**
+
+**char* notcurses_hostname(void);**
+
+# DESCRIPTION
+
+Notcurses provides some utility functions, usually to abstract away
+platform-dependent differences.
+
+**notcurses_accountname** returns a heap-allocated copy of the account
+name under which the program is running. **notcurses_hostname** returns
+a heap-allocated copy of the local host name.
+
+# NOTES
+
+# RETURN VALUES
+
+All functions return ***NULL*** on error.
+
+# SEE ALSO
+
+**hostname(1)**,
+**notcurses(3)**

include/notcurses/notcurses.h

@@ -94,6 +94,12 @@ typedef enum {
 // -1 if a non-printable/illegal character is encountered.
 API int ncstrwidth(const char* mbs);
 
+// Returns a heap-allocated copy of the user name under which we are running.
+API ALLOC char* notcurses_accountname(void);
+
+// Returns a heap-allocated copy of the local host name.
+API ALLOC char* notcurses_hostname(void);
+
 // input functions like notcurses_get() return ucs32-encoded uint32_t. convert
 // a series of uint32_t to utf8. result must be at least 4 bytes per input
 // uint32_t (6 bytes per uint32_t will future-proof against Unicode expansion).

src/lib/aux.c

@@ -0,0 +1,51 @@
+#ifndef __MINGW64__
+#include <pwd.h>
+#include <unistd.h>
+#endif
+#include "internal.h"
+
+char* notcurses_accountname(void){
+#ifndef __MINGW64__
+  const char* un;
+  if( (un = getenv("LOGNAME")) ){
+    return strdup(un);
+  }
+  uid_t uid = getuid();
+  struct passwd* p = getpwuid(uid);
+  if(p == NULL){
+    return NULL;
+  }
+  return strdup(p->pw_name);
+#else
+  DWORD unlen = UNLEN + 1;
+  char* un = malloc(unlen);
+  if(un == NULL){
+    return NULL;
+  }
+  if(GetUserName(un, &unlen)){ // FIXME probably want GetUserNameEx
+    free(un);
+    return NULL;
+  }
+  return un;
+#endif
+}
+
+char* notcurses_hostname(void){
+#ifndef __MINGW64__
+  char hostname[_POSIX_HOST_NAME_MAX + 1];
+  if(gethostname(hostname, sizeof(hostname)) == 0){
+    char* fqdn = strchr(hostname, '.');
+    if(fqdn){
+      *fqdn = '\0';
+    }
+    return strdup(hostname);
+  }
+#else // windows
+  char lp[MAX_COMPUTERNAME_LENGTH + 1];
+  size_t s = sizeof(lp);
+  if(GetComputerNameA(lp, &s)){
+    return strdup(lp);
+  }
+#endif
+  return NULL;
+}