Provide a termkey_lookup_keyname that can do partial buffer parsing

t/10keyname.c

@@ -5,8 +5,9 @@ int main(int argc, char *argv[])
 {
   TermKey   *tk;
   TermKeySym sym;
+  char *end;
 
-  plan_tests(3);
+  plan_tests(10);
 
   tk = termkey_new(0, TERMKEY_FLAG_NOTERMIOS);
 
@@ -16,6 +17,19 @@ int main(int argc, char *argv[])
   sym = termkey_keyname2sym(tk, "SomeUnknownKey");
   is_int(sym, TERMKEY_SYM_UNKNOWN, "keyname2sym SomeUnknownKey");
 
+  end = termkey_lookup_keyname(tk, "Up", &sym);
+  ok(!!end, "termkey_get_keyname Up returns non-NULL");
+  is_str(end, "", "termkey_get_keyname Up return points at endofstring");
+  is_int(sym, TERMKEY_SYM_UP, "termkey_get_keyname Up yields Up symbol");
+
+  end = termkey_lookup_keyname(tk, "DownMore", &sym);
+  ok(!!end, "termkey_get_keyname DownMore returns non-NULL");
+  is_str(end, "More", "termkey_get_keyname DownMore return points at More");
+  is_int(sym, TERMKEY_SYM_DOWN, "termkey_get_keyname DownMore yields Down symbol");
+
+  end = termkey_lookup_keyname(tk, "SomeUnknownKey", &sym);
+  ok(!end, "termkey_get_keyname SomeUnknownKey returns NULL");
+
   is_str(termkey_get_keyname(tk, TERMKEY_SYM_SPACE), "Space", "get_keyname SPACE");
 
   termkey_destroy(tk);

termkey.c

@@ -914,18 +914,30 @@ const char *termkey_get_keyname(TermKey *tk, TermKeySym sym)
   return "UNKNOWN";
 }
 
-TermKeySym termkey_keyname2sym(TermKey *tk, const char *keyname)
+char *termkey_lookup_keyname(TermKey *tk, const char *str, TermKeySym *sym)
 {
   /* We store an array, so we can't do better than a linear search. Doesn't
    * matter because user won't be calling this too often */
 
+  for(*sym = 0; *sym < tk->nkeynames; (*sym)++) {
+    const char *thiskey = tk->keynames[*sym];
+    if(!thiskey)
+      continue;
+    size_t len = strlen(thiskey);
+    if(strncmp(str, thiskey, len) == 0)
+      return (char *)str + len;
+  }
+
+  return NULL;
+}
+
+TermKeySym termkey_keyname2sym(TermKey *tk, const char *keyname)
+{
   TermKeySym sym;
-
-  for(sym = 0; sym < tk->nkeynames; sym++)
-    if(tk->keynames[sym] && strcmp(keyname, tk->keynames[sym]) == 0)
-      return sym;
-
-  return TERMKEY_SYM_UNKNOWN;
+  char *endp = termkey_lookup_keyname(tk, keyname, &sym);
+  if(!endp || endp[0])
+    return TERMKEY_SYM_UNKNOWN;
+  return sym;
 }
 
 static TermKeySym register_c0(TermKey *tk, TermKeySym sym, unsigned char ctrl, const char *name)

termkey.h.in

@@ -171,11 +171,12 @@ TermKeyResult termkey_advisereadable(TermKey *tk);
 
 TermKeySym termkey_register_keyname(TermKey *tk, TermKeySym sym, const char *name);
 const char *termkey_get_keyname(TermKey *tk, TermKeySym sym);
-
-TermKeyResult termkey_interpret_mouse(TermKey *tk, TermKeyKey *key, TermKeyMouseEvent *event, int *button, int *line, int *col);
+char       *termkey_lookup_keyname(TermKey *tk, const char *str, TermKeySym *sym);
 
 TermKeySym termkey_keyname2sym(TermKey *tk, const char *keyname); 
 
+TermKeyResult termkey_interpret_mouse(TermKey *tk, TermKeyKey *key, TermKeyMouseEvent *event, int *button, int *line, int *col);
+
 typedef enum {
   TERMKEY_FORMAT_LONGMOD     = 1 << 0, // Shift-... instead of S-...
   TERMKEY_FORMAT_CARETCTRL   = 1 << 1, // ^X instead of C-X

termkey_get_keyname.3

@@ -17,5 +17,6 @@ Link with \fI-ltermkey\fP.
 .BR termkey_new (3),
 .BR termkey_getkey (3),
 .BR termkey_waitkey (3),
+.BR termkey_lookup_keyname (3),
 .BR termkey_keyname2sym (3),
 .BR termkey_strfkey (3)

termkey_keyname2sym.3

@@ -10,13 +10,13 @@ termkey_keyname2sym \- look up a symbolic key value for a string name
 .sp
 Link with \fI-ltermkey\fP.
 .SH DESCRIPTION
-\fBtermkey_keyname2sym\fP looks up the symbolic key value represented by the given string name. This is a case-sensitive comparison. If the given name is not found, \fBTERMKEY_SYM_UNKNOWN\fP is returned instead. This function is the inverse of \fBtermkey_get_keyname\fP(3).
+\fBtermkey_keyname2sym\fP looks up the symbolic key value represented by the given string name. This is a case-sensitive comparison. If the given name is not found, \fBTERMKEY_SYM_UNKNOWN\fP is returned instead. This function is the inverse of \fBtermkey_get_keyname\fP(3), and is a more specific form of \fBtermkey_lookup_keyname\fP(3) which only recognises names as complete strings.
 .PP
 Because the key names are stored in an array indexed by the symbol number, this function has to perform a linear search of the names. Use of this function should be restricted to converting key names into symbolic values during a program's initialisation, so that efficient comparisons can be done while it is running.
 .SH "RETURN VALUE"
-\fBtermkey_get_key\fP() returns a pointer to a string.
+\fBtermkey_keyname2sym\fP() returns a symbolic key constant, or \fBTERMKEY_SYM_UNKNOWN\fP.
 .SH "SEE ALSO"
 .BR termkey_new (3),
 .BR termkey_get_keyname (3),
-.BR termkey_strfkey (3),
+.BR termkey_lookup_keyname (3),
 .BR termkey_strpkey (3)

termkey_lookup_keyname.3

@@ -0,0 +1,23 @@
+.TH TERMKEY_LOOKUP_KEYNAME 3
+.SH NAME
+termkey_lookup_keyname \- look up a symbolic key value for a string name
+.SH SYNOPSIS
+.nf
+.B #include <termkey.h>
+.sp
+.BI "char *termkey_lookup_keyname(TermKey *" tk ", const char *" keyname ",
+.BI "           TermKeySym *" sym ");
+.fi
+.sp
+Link with \fI-ltermkey\fP.
+.SH DESCRIPTION
+\fBtermkey_lookup_keyname\fP looks up the symbolic key value represented by the given string name. This is a case-sensitive comparison. The symbolic value is written to the variable addressed by \fIsym\fP. This function is a more general form of \fBtermkey_keyname2sym\fP(3) because it can recognise a symbolic key name within a longer string, returning a pointer to the remainder of the input after the key name.
+.PP
+Because the key names are stored in an array indexed by the symbol number, this function has to perform a linear search of the names. Use of this function should be restricted to converting key names into symbolic values during a program's initialisation, so that efficient comparisons can be done while it is running.
+.SH "RETURN VALUE"
+\fBtermkey_lookup_keyname\fP() returns a pointer to the first character after a recognised name, or \fBNULL\fP if the string does not begin with the name of a recognised symbolic key.
+.SH "SEE ALSO"
+.BR termkey_new (3),
+.BR termkey_get_keyname (3),
+.BR termkey_keyname2sym (3),
+.BR termkey_strpkey (3)