New header file 'defs.h'.

This centralises a few things that multiple header files were
previously defining, and were protecting against each other's
redefinition with ifdefs - small things like structs and typedefs. Now
all those things are in a defs.h which is by definition safe to
include _first_ (out of all the codebase-local headers) and only need
to be defined once.

defs.h

@@ -0,0 +1,37 @@
+/*
+ * defs.h: initial definitions for PuTTY.
+ *
+ * The rule about this header file is that it can't depend on any
+ * other header file in this code base. This is where we define
+ * things, as much as we can, that other headers will want to refer
+ * to, such as opaque structure types and their associated typedefs,
+ * or macros that are used by other headers.
+ */
+
+#ifndef PUTTY_DEFS_H
+#define PUTTY_DEFS_H
+
+typedef struct conf_tag Conf;
+typedef struct backend_tag Backend;
+typedef struct terminal_tag Terminal;
+
+typedef struct Filename Filename;
+typedef struct FontSpec FontSpec;
+
+typedef struct bufchain_tag bufchain;
+
+typedef struct strbuf strbuf;
+
+struct RSAKey;
+
+#include <stdint.h>
+typedef uint32_t uint32;
+
+/* Do a compile-time type-check of 'to_check' (without evaluating it),
+ * as a side effect of returning the value 'to_return'. Note that
+ * although this macro double-*expands* to_return, it always
+ * *evaluates* exactly one copy of it, so it's side-effect safe. */
+#define TYPECHECK(to_check, to_return)                  \
+    (sizeof(to_check) ? (to_return) : (to_return))
+
+#endif /* PUTTY_DEFS_H */

misc.h

@@ -5,6 +5,7 @@
 #ifndef PUTTY_MISC_H
 #define PUTTY_MISC_H
 
+#include "defs.h"
 #include "puttymem.h"
 
 #include <stdio.h>		       /* for FILE * */
@@ -18,9 +19,6 @@
 #define TRUE 1
 #endif
 
-typedef struct Filename Filename;
-typedef struct FontSpec FontSpec;
-
 unsigned long parse_blocksize(const char *bs);
 char ctrlparse(char *s, char **next);
 
@@ -38,7 +36,7 @@ char *dupprintf(const char *fmt, ...)
     ;
 char *dupvprintf(const char *fmt, va_list ap);
 void burnstr(char *string);
-typedef struct strbuf strbuf;
+
 strbuf *strbuf_new(void);
 void strbuf_free(strbuf *buf);
 char *strbuf_str(strbuf *buf);         /* does not free buf */
@@ -70,10 +68,6 @@ struct bufchain_tag {
     struct bufchain_granule *head, *tail;
     int buffersize;		       /* current amount of buffered data */
 };
-#ifndef BUFCHAIN_TYPEDEF
-typedef struct bufchain_tag bufchain;  /* rest of declaration in misc.c */
-#define BUFCHAIN_TYPEDEF
-#endif
 
 void bufchain_init(bufchain *ch);
 void bufchain_clear(bufchain *ch);

network.h

@@ -13,12 +13,7 @@
 #ifndef PUTTY_NETWORK_H
 #define PUTTY_NETWORK_H
 
-#ifndef DONE_TYPEDEFS
-#define DONE_TYPEDEFS
-typedef struct conf_tag Conf;
-typedef struct backend_tag Backend;
-typedef struct terminal_tag Terminal;
-#endif
+#include "defs.h"
 
 typedef struct SockAddr_tag *SockAddr;
 /* pay attention to levels of indirection */
@@ -229,10 +224,6 @@ Socket new_error_socket(const char *errmsg, Plug plug);
 void backend_socket_log(void *frontend, int type, SockAddr addr, int port,
                         const char *error_msg, int error_code, Conf *conf,
                         int session_started);
-#ifndef BUFCHAIN_TYPEDEF
-typedef struct bufchain_tag bufchain;  /* rest of declaration in misc.c */
-#define BUFCHAIN_TYPEDEF
-#endif
 void log_proxy_stderr(Plug plug, bufchain *buf, const void *vdata, int len);
 
 #endif

putty.h

@@ -16,13 +16,7 @@
 #endif
 #endif
 
-#ifndef DONE_TYPEDEFS
-#define DONE_TYPEDEFS
-typedef struct conf_tag Conf;
-typedef struct backend_tag Backend;
-typedef struct terminal_tag Terminal;
-#endif
-
+#include "defs.h"
 #include "puttyps.h"
 #include "network.h"
 #include "misc.h"
@@ -538,8 +532,6 @@ GLOBAL int loaded_session;
  */
 GLOBAL char *cmdline_session_name;
 
-struct RSAKey;			       /* be a little careful of scope */
-
 /*
  * Mechanism for getting text strings such as usernames and passwords
  * from the front-end.

ssh.h

@@ -199,11 +199,6 @@ unsigned char *rsa_ssh1_public_blob(struct RSAKey *key, int *len,
 int rsa_public_blob_len(void *data, int maxlen);
 void freersakey(struct RSAKey *key);
 
-#ifndef PUTTY_UINT32_DEFINED
-/* This makes assumptions about the int type. */
-typedef unsigned int uint32;
-#define PUTTY_UINT32_DEFINED
-#endif
 typedef uint32 word32;
 
 unsigned long crc32_compute(const void *s, size_t len);

unix/unix.h

@@ -71,9 +71,6 @@ extern Backend pty_backend;
 
 #define BROKEN_PIPE_ERROR_CODE EPIPE   /* used in sshshare.c */
 
-typedef uint32_t uint32; /* C99: uint32_t defined in stdint.h */
-#define PUTTY_UINT32_DEFINED
-
 /*
  * Under GTK, we send MA_CLICK _and_ MA_2CLK, or MA_CLICK _and_
  * MA_3CLK, when a button is pressed for the second or third time.

windows/winstuff.h

@@ -23,6 +23,8 @@
 #include <stdint.h>
 #endif
 
+#include "defs.h"
+
 #include "tree234.h"
 
 #include "winhelp.h"
@@ -132,8 +134,6 @@ struct FontSpec *fontspec_new(const char *name,
  *
  * (DECL_WINDOWS_FUNCTION works with both these variants.)
  */
-#define TYPECHECK(to_check, to_return)          \
-    (sizeof(to_check) ? to_return : to_return)
 #define DECL_WINDOWS_FUNCTION(linkage, rettype, name, params)   \
     typedef rettype (WINAPI *t_##name) params;                  \
     linkage t_##name p_##name
@@ -164,13 +164,6 @@ struct FontSpec *fontspec_new(const char *name,
 #endif
 #endif
 
-#ifndef DONE_TYPEDEFS
-#define DONE_TYPEDEFS
-typedef struct conf_tag Conf;
-typedef struct backend_tag Backend;
-typedef struct terminal_tag Terminal;
-#endif
-
 #define PUTTY_REG_POS "Software\\SimonTatham\\PuTTY"
 #define PUTTY_REG_PARENT "Software\\SimonTatham"
 #define PUTTY_REG_PARENT_CHILD "PuTTY"
@@ -198,9 +191,6 @@ typedef struct terminal_tag Terminal;
 
 typedef HDC Context;
 
-typedef unsigned int uint32; /* int is 32-bits on Win32 and Win64. */
-#define PUTTY_UINT32_DEFINED
-
 #ifndef NO_GSSAPI
 /*
  * GSS-API stuff