diff options
Diffstat (limited to 'windows/help.c')
| -rw-r--r-- | windows/help.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/windows/help.c b/windows/help.c new file mode 100644 index 00000000..d087c722 --- /dev/null +++ b/windows/help.c @@ -0,0 +1,250 @@ +/* + * help.c: centralised functions to launch Windows HTML Help files. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <assert.h> + +#include "putty.h" +#include "putty-rc.h" + +#ifdef NO_HTMLHELP + +/* If htmlhelp.h is not available, we can't do any of this at all */ +bool has_help(void) { return false; } +void init_help(void) { } +void shutdown_help(void) { } +void launch_help(HWND hwnd, const char *topic) { } +void quit_help(HWND hwnd) { } + +#else + +#include <htmlhelp.h> + +static char *chm_path = NULL; +static bool chm_created_by_us = false; + +static bool requested_help; +DECL_WINDOWS_FUNCTION(static, HWND, HtmlHelpA, (HWND, LPCSTR, UINT, DWORD_PTR)); + +static HRSRC chm_hrsrc; +static DWORD chm_resource_size = 0; +static const void *chm_resource = NULL; + +int has_embedded_chm(void) +{ + static bool checked = false; + if (!checked) { + checked = true; + + chm_hrsrc = FindResource( + NULL, MAKEINTRESOURCE(ID_CUSTOM_CHMFILE), + MAKEINTRESOURCE(TYPE_CUSTOM_CHMFILE)); + } + return chm_hrsrc != NULL ? 1 : 0; +} + +static bool find_chm_resource(void) +{ + static bool checked = false; + if (checked) /* we've been here already */ + goto out; + checked = true; + + /* + * Look for a CHM file embedded in this executable as a custom + * resource. + */ + if (!has_embedded_chm()) /* set up chm_hrsrc and check if it's NULL */ + goto out; + + chm_resource_size = SizeofResource(NULL, chm_hrsrc); + if (chm_resource_size == 0) + goto out; + + HGLOBAL chm_hglobal = LoadResource(NULL, chm_hrsrc); + if (chm_hglobal == NULL) + goto out; + + chm_resource = (const uint8_t *)LockResource(chm_hglobal); + + out: + return chm_resource != NULL; +} + +static bool load_chm_resource(void) +{ + bool toret = false; + char *filename = NULL; + HANDLE filehandle = INVALID_HANDLE_VALUE; + bool created = false; + + static bool tried_to_load = false; + if (tried_to_load) + goto out; + tried_to_load = true; + + /* + * We've found it! Now write it out into a separate file, so that + * htmlhelp.exe can handle it. + */ + + /* GetTempPath is documented as returning a size of up to + * MAX_PATH+1 which does not count the NUL */ + char tempdir[MAX_PATH + 2]; + if (GetTempPath(sizeof(tempdir), tempdir) == 0) + goto out; + + unsigned long pid = GetCurrentProcessId(); + + for (uint64_t counter = 0;; counter++) { + filename = dupprintf( + "%s\\putty_%lu_%"PRIu64".chm", tempdir, pid, counter); + filehandle = CreateFile( + filename, GENERIC_WRITE, FILE_SHARE_READ, + NULL, CREATE_NEW, FILE_ATTRIBUTE_NORMAL, NULL); + + if (filehandle != INVALID_HANDLE_VALUE) + break; /* success! */ + + if (GetLastError() != ERROR_FILE_EXISTS) + goto out; /* failed for some other reason! */ + + sfree(filename); + filename = NULL; + } + created = true; + + const uint8_t *p = (const uint8_t *)chm_resource; + for (DWORD pos = 0; pos < chm_resource_size; pos++) { + DWORD to_write = chm_resource_size - pos; + DWORD written = 0; + + if (!WriteFile(filehandle, p + pos, to_write, &written, NULL)) + goto out; + pos += written; + } + + chm_path = filename; + filename = NULL; + chm_created_by_us = true; + toret = true; + + out: + if (created && !toret) + DeleteFile(filename); + sfree(filename); + if (filehandle != INVALID_HANDLE_VALUE) + CloseHandle(filehandle); + return toret; +} + +static bool find_chm_from_installation(void) +{ + static const char *const reg_paths[] = { + "Software\\SimonTatham\\PuTTY64\\CHMPath", + "Software\\SimonTatham\\PuTTY\\CHMPath", + }; + + for (size_t i = 0; i < lenof(reg_paths); i++) { + char *filename = get_reg_sz_simple( + HKEY_LOCAL_MACHINE, reg_paths[i], NULL); + + if (filename) { + chm_path = filename; + chm_created_by_us = false; + return true; + } + } + + return false; +} + +void init_help(void) +{ + /* Just in case of multiple calls */ + static bool already_called = false; + if (already_called) + return; + already_called = true; + + /* + * Don't even try looking for the CHM file if we can't even find + * the HtmlHelp() API function. + */ + HINSTANCE dllHH = load_system32_dll("hhctrl.ocx"); + GET_WINDOWS_FUNCTION(dllHH, HtmlHelpA); + if (!p_HtmlHelpA) { + FreeLibrary(dllHH); + return; + } + + /* + * If there's a CHM file embedded in this executable, we should + * use that as the first choice. + */ + if (find_chm_resource()) + return; + + /* + * Otherwise, try looking for the CHM in the location that the + * installer marked in the registry. + */ + if (find_chm_from_installation()) + return; +} + +void shutdown_help(void) +{ + if (chm_path && chm_created_by_us) { + p_HtmlHelpA(NULL, NULL, HH_CLOSE_ALL, 0); + DeleteFile(chm_path); + } + sfree(chm_path); + chm_path = NULL; + chm_created_by_us = false; +} + +bool has_help(void) +{ + return chm_path != NULL || chm_resource != NULL; +} + +void launch_help(HWND hwnd, const char *topic) +{ + if (!chm_path && chm_resource) { + /* + * If we've been called without already having a file name for + * the CHM file, that might be because we've located it in our + * resource section but not written it to a temp file yet. Do + * so now, on first use. + */ + load_chm_resource(); + } + + /* If we _still_ don't have a CHM pathname, we just can't display help. */ + if (!chm_path) + return; + + if (topic) { + char *fname = dupprintf( + "%s::/%s.html>main", chm_path, topic); + p_HtmlHelpA(hwnd, fname, HH_DISPLAY_TOPIC, 0); + sfree(fname); + } else { + p_HtmlHelpA(hwnd, chm_path, HH_DISPLAY_TOPIC, 0); + } + requested_help = true; +} + +void quit_help(HWND hwnd) +{ + if (requested_help) + p_HtmlHelpA(NULL, NULL, HH_CLOSE_ALL, 0); + if (chm_path && chm_created_by_us) + DeleteFile(chm_path); +} + +#endif /* NO_HTMLHELP */ |