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diff --git a/Lessons/Lesson_59/README.md b/Lessons/Lesson_59/README.md deleted file mode 100644 index 1ac4b3c..0000000 --- a/Lessons/Lesson_59/README.md +++ /dev/null @@ -1,102 +0,0 @@ -Now let's try to actually save some user input with a form. - -For the data we will choose the most simple element - checkbox (https://edk2-docs.gitbook.io/edk-ii-vfr-specification/2_vfr_description_in_bnf/211_vfr_form_definition#2.11.6.5.1-vfr-checkbox-statement-definition) - -Crete new application with a form and insert the following code inside: -``` -checkbox - prompt = STRING_TOKEN(CHECKBOX_TITLE), - help = STRING_TOKEN(CHECKBOX_HELP), -endcheckbox; -``` - -This will give you the following element on form - - - -Which you can toggle with a spacebar - - - -The checkbox element will produce `EFI_IFR_CHECKBOX` and `EFI_IFR_END` opcodes: -``` - checkbox ->00000039: 06 8E 05 00 06 00 01 00 00 00 FF FF 00 00 - prompt = STRING_TOKEN(0x0005), - help = STRING_TOKEN(0x0006), - endcheckbox; ->00000047: 29 02 -``` - -Here is a definition for the `EFI_IFR_CHECKBOX`: -``` -EFI_IFR_CHECKBOX - -Summary: -Creates a boolean checkbox. - -Prototype: - -#define EFI_IFR_CHECKBOX_OP 0x06 - -typedef struct _EFI_IFR_CHECKBOX { - EFI_IFR_OP_HEADER Header; - EFI_IFR_QUESTION_HEADER Question; - UINT8 Flags; -} EFI_IFR_CHECKBOX; - -Members: -Header The standard question header, where Header.OpCode = EFI_IFR_CHECKBOX_OP. -Question The standard question header. -Flags Flags that describe the behavior of the question. All undefined bits should be zero. - -Description: -Creates a Boolean checkbox question and adds it to the current form. The checkbox has two values: -FALSE if the box is not checked and TRUE if it is. -``` -And for its field `EFI_IFR_QUESTION_HEADER`: -``` -EFI_IFR_QUESTION_HEADER - -Summary: -Standard question header. - -Prototype: - -typedef struct _EFI_IFR_QUESTION_HEADER { - EFI_IFR_STATEMENT_HEADER Header; - EFI_QUESTION_ID QuestionId; - EFI_VARSTORE_ID VarStoreId; - union { - EFI_STRING_ID VarName; - UINT16 VarOffset; - } VarStoreInfo; - UINT8 Flags; -} EFI_IFR_QUESTION_HEADER; - -Members: -Header The standard statement header. -QuestionId The unique value that identifies the particular question being defined by the opcode. The value of zero is reserved. -Flags A bit-mask that determines which unique settings are active for this question. -VarStoreId Specifies the identifier of a previously declared variable store to use when storing the question’s value. - A value of zero indicates no associated variable store. -VarStoreInfo If VarStoreId refers to Buffer Storage (EFI_IFR_VARSTORE or EFI_IFR_VARSTORE_EFI), then VarStoreInfo contains a 16-bit Buffer Storage offset (VarOffset). - If VarStoreId refers to Name/Value Storage (EFI_IFR_VARSTORE_NAME_VALUE), then VarStoreInfo contains the String ID of the name (VarName) for this name/value pair. - -Description -This is the standard header for questions. -``` - -# Creating `efivarstore` - - - -FS0:\> dmpstore -all -``` -Variable NV+BS 'EF2ACC91-7B50-4AB9-AB67-2B04F8BC135E:HIIFormCheckboxEfiVarstore' DataSize = 0x01 - 00000000: 01 *.* -``` - -FS0:\> dmpstore -guid EF2ACC91-7B50-4AB9-AB67-2B04F8BC135E -Variable NV+BS 'EF2ACC91-7B50-4AB9-AB67-2B04F8BC135E:HIIFormCheckboxEfiVarstore' DataSize = 0x01 - 00000000: 01 *.* |