Allow expansion of environment variables in lesskey files,

using the syntax ${NAME} and ${NAME/STRING/REPL}.
Change lesskey parsing so that definitions override earlier definitions.

Makefile.aut

@@ -17,7 +17,7 @@ endif
 
 SRC = \
  main.c screen.c brac.c ch.c charset.c cmdbuf.c \
- command.c cvt.c decode.c edit.c filename.c forwback.c \
+ command.c cvt.c decode.c edit.c evar.c filename.c forwback.c \
  help.c ifile.c input.c jump.c line.c linenum.c \
  lsystem.c mark.c optfunc.c option.c opttbl.c os.c \
  output.c pattern.c position.c prompt.c search.c signal.c \

Makefile.in

@@ -48,7 +48,7 @@ SHELL = /bin/sh
 
 OBJ = \
  main.${O} screen.${O} brac.${O} ch.${O} charset.${O} cmdbuf.${O} \
- command.${O} cvt.${O} decode.${O} edit.${O} filename.${O} forwback.${O} \
+ command.${O} cvt.${O} decode.${O} edit.${O} evar.${O} filename.${O} forwback.${O} \
  help.${O} ifile.${O} input.${O} jump.${O} \
  line.${O} linenum.${O} \
  lsystem.${O} mark.${O} optfunc.${O} option.${O} opttbl.${O} os.${O} \

NEWS

@@ -17,6 +17,10 @@
 
 * Add --lesskey-content option (github #447).
 
+* Add LESSKEY_CONTENT environment variable.
+
+* Allow expansion of environment variables in lesskey files.
+
 * Add LESSSECURE_ALLOW environment variable (github #449).
 
 * Mouse right-click jumps to position marked by left-click (github #390).

decode.c

@@ -37,6 +37,8 @@ extern int erase_char, erase2_char, kill_char;
 extern int mousecap;
 extern int sc_height;
 
+static void add_content_table(int (*call_lesskey)(char *, int), char *envname, int sysvar);
+
 #define SK(k) \
  SK_SPECIAL_KEY, (k), 6, 1, 1, 1
 /*
@@ -319,7 +321,6 @@ public void expand_cmd_tables(void)
  expand_cmd_table(list_sysvar_tables);
 }
 
-
 /*
  * Initialize the command lists.
  */
@@ -367,6 +368,9 @@ public void init_cmds(void)
  add_hometable(lesskey, "LESSKEY", LESSKEYFILE, 0);
  }
 #endif
+
+ add_content_table(lesskey_content, "LESSKEY_CONTENT_SYSTEM", 1);
+ add_content_table(lesskey_content, "LESSKEY_CONTENT", 0);
 }
 
 /*
@@ -389,11 +393,42 @@ static int add_cmd_table(struct tablelist **tlist, char *buf, int len)
  }
  t->t_start = buf;
  t->t_end = buf + len;
- t->t_next = *tlist;
- *tlist = t;
+ t->t_next = NULL;
+ if (*tlist == NULL)
+ *tlist = t;
+ else
+ {
+ struct tablelist *e;
+ for (e = *tlist; e->t_next != NULL; e = e->t_next)
+ continue;
+ e->t_next = t;
+ }
  return (0);
 }
 
+/*
+ * Remove the last command table in a list.
+ */
+static void pop_cmd_table(struct tablelist **tlist)
+{
+ struct tablelist *t;
+ if (*tlist == NULL)
+ return;
+ if ((*tlist)->t_next == NULL)
+ {
+ t = *tlist;
+ *tlist = NULL;
+ } else
+ {
+ struct tablelist *e;
+ for (e = *tlist; e->t_next->t_next != NULL; e = e->t_next)
+ continue;
+ t = e->t_next;
+ e->t_next = NULL;
+ }
+ free(t);
+}
+
 /*
  * Add a command table.
  */
@@ -417,7 +452,11 @@ public void add_ecmd_table(char *buf, int len)
  */
 static void add_var_table(struct tablelist **tlist, char *buf, int len)
 {
- if (add_cmd_table(tlist, buf, len) < 0)
+ struct xbuffer xbuf;
+
+ xbuf_init(&xbuf);
+ expand_evars(buf, len, &xbuf);
+ if (add_cmd_table(tlist, xbuf_char_data(&xbuf), xbuf.end) < 0)
  error("Warning: environment variables from lesskey file unavailable", NULL_PARG);
 }
 
@@ -566,7 +605,7 @@ static int cmd_search(char *cmd, char *table, char *endtable, char **sp)
 {
  char *p;
  char *q;
- int a;
+ int a = A_INVALID;
 
  *sp = NULL;
  for (p = table, q = cmd; p < endtable; p++, q++)
@@ -601,13 +640,15 @@ static int cmd_search(char *cmd, char *table, char *endtable, char **sp)
  if (a & A_EXTRA)
  {
  *sp = ++p;
+ while (*p != '\0')
+ ++p;
  a &= ~A_EXTRA;
  }
  if (a == A_X11MOUSE_IN)
  a = x11mouse_action(0);
  else if (a == A_X116MOUSE_IN)
  a = x116mouse_action(0);
- return (a);
+ q = cmd-1;
  }
  } else if (*q == '\0')
  {
@@ -643,10 +684,7 @@ static int cmd_search(char *cmd, char *table, char *endtable, char **sp)
  q = cmd-1;
  }
  }
- /*
- * No match found in the entire command table.
- */
- return (A_INVALID);
+ return (a);
 }
 
 /*
@@ -659,17 +697,22 @@ static int cmd_decode(struct tablelist *tlist, char *cmd, char **sp)
  int action = A_INVALID;
 
  /*
- * Search thru all the command tables.
- * Stop when we find an action which is not A_INVALID.
+ * Search for the cmd thru all the command tables.
+ * If we find it more than once, take the last one.
  */
+ *sp = NULL;
  for (t = tlist; t != NULL; t = t->t_next)
  {
- action = cmd_search(cmd, t->t_start, t->t_end, sp);
- if (action != A_INVALID)
- break;
+ char *tsp;
+ int taction = cmd_search(cmd, t->t_start, t->t_end, &tsp);
+ if (taction == A_UINVALID)
+ taction = A_INVALID;
+ if (taction != A_INVALID)
+ {
+ action = taction;
+ *sp = tsp;
+ }
  }
- if (action == A_UINVALID)
- action = A_INVALID;
  return (action);
 }
 
@@ -710,6 +753,38 @@ public char * lgetenv(char *var)
  return (NULL);
 }
 
+/*
+ * Like lgetenv, but also uses a buffer partially filled with an env table.
+ */
+public char * lgetenv_ext(char *var, char *env_buf, int env_buf_len)
+{
+ char *r;
+ int e;
+ int env_end = 0;
+
+ for (e = 0;;)
+ {
+ for (; e < env_buf_len; e++)
+ if (env_buf[e] == '\0')
+ break;
+ if (e >= env_buf_len) break;
+ if (env_buf[++e] & A_EXTRA)
+ {
+ for (e = e+1; e < env_buf_len; e++)
+ if (env_buf[e] == '\0')
+ break;
+ }
+ e++;
+ if (e >= env_buf_len) break;
+ env_end = e;
+ }
+ /* Temporarily add env_buf to var_tables, do the lookup, then remove it. */
+ add_var_table(&list_var_tables, env_buf, env_end);
+ r = lgetenv(var);
+ pop_cmd_table(&list_var_tables);
+ return r;
+}
+
 /*
  * Is a string null or empty? 
  */
@@ -946,7 +1021,18 @@ public int add_hometable(int (*call_lesskey)(char *, int), char *envname, char *
  free(filename);
  return (r);
 }
-#endif
+
+/*
+ * Add the content of a lesskey source file.
+ */
+static void add_content_table(int (*call_lesskey)(char *, int), char *envname, int sysvar)
+{
+ char *content = lgetenv(envname);
+ if (isnullenv(content))
+ return;
+ lesskey_content(content, sysvar);
+}
+#endif /* USERFILE */
 
 /*
  * See if a char is a special line-editing command.