diff options
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/libcacard.txt | 26 | ||||
| -rw-r--r-- | docs/tracing.txt | 48 |
2 files changed, 54 insertions, 20 deletions
diff --git a/docs/libcacard.txt b/docs/libcacard.txt index f7d7519f3a..8db421d3a9 100644 --- a/docs/libcacard.txt +++ b/docs/libcacard.txt @@ -10,7 +10,7 @@ such as signing, card removal/insertion, etc. are mapped to real, physical cards which are shared with the client machine the emulator is running on, or the cards could be pure software constructs. -The emulator is structured to allow multiple replacable or additional pieces, +The emulator is structured to allow multiple replaceable or additional pieces, so it can be easily modified for future requirements. The primary envisioned modifications are: @@ -32,7 +32,7 @@ be emulated as well, including PIV, newer versions of CAC, PKCS #15, etc. -------------------- Replacing the Socket Based Virtual Reader Interface. -The current implementation contains a replacable module vscclient.c. The +The current implementation contains a replaceable module vscclient.c. The current vscclient.c implements a sockets interface to the virtual ccid reader on the guest. CCID commands that are pertinent to emulation are passed across the socket, and their responses are passed back along that same socket. @@ -42,7 +42,7 @@ implements a program with a main entry. It also handles argument parsing for the emulator. An application that wants to use the virtual reader can replace vscclient.c -with it's own implementation that connects to it's own CCID reader. The calls +with its own implementation that connects to its own CCID reader. The calls that the CCID reader can call are: VReaderList * vreader_get_reader_list(); @@ -72,12 +72,12 @@ that the CCID reader can call are: VReader * vreader_list_get_reader(VReaderListEntry *) This function returns the reader stored in the reader List entry. Caller gets - a new reference to a reader. The caller must free it's reference when it is + a new reference to a reader. The caller must free its reference when it is finished with vreader_free(). void vreader_free(VReader *reader); - This function frees a reference to a reader. Reader's are reference counted + This function frees a reference to a reader. Readers are reference counted and are automatically deleted when the last reference is freed. void vreader_list_delete(VReaderList *list); @@ -87,7 +87,7 @@ that the CCID reader can call are: VReaderStatus vreader_power_on(VReader *reader, char *atr, int *len); - This functions simulates a card power on. Virtual cards do not care about + This function simulates a card power on. A virtual card does not care about the actual voltage and other physical parameters, but it does care that the card is actually on or off. Cycling the card causes the card to reset. If the caller provides enough space, vreader_power_on will return the ATR of @@ -104,7 +104,7 @@ that the CCID reader can call are: unsigned char *receive_buf, int receive_buf_len); - This functions send a raw apdu to a card and returns the card's response. + This function sends a raw apdu to a card and returns the card's response. The CCID front end should return the response back. Most of the emulation is driven from these APDUs. @@ -217,10 +217,10 @@ the card using the following functions: VCardStatus vcard_add_applet(VCard *card, VCardApplet *applet); Add an applet onto the list of applets attached to the card. Once an applet - has been added, it can be selected by it's aid, and then commands will be - routed to it VCardProcessAPDU function. This function adopts the applet the - passed int applet. Note: 2 applets with the same AID should not be added to - the same card. It's permissible to add more than one applet. Multiple applets + has been added, it can be selected by its AID, and then commands will be + routed to it VCardProcessAPDU function. This function adopts the applet that + is passed into it. Note: 2 applets with the same AID should not be added to + the same card. It is permissible to add more than one applet. Multiple applets may have the same VCardPRocessAPDU entry point. The certs and keys should be attached to private data associated with one or @@ -335,7 +335,7 @@ and applet. VCard7816Status vcard_emul_login(VCard *card, unsigned char *pin, int pin_len); - This function logins into the card and return the standard 7816 status + This function logs into the card and returns the standard 7816 status word depending on the success or failure of the call. void vcard_emul_delete_key(VCardKey *key); @@ -424,7 +424,7 @@ functions: cert_len, and keys are all arrays of length cert_count. These are the the same of the parameters xxxx_card_init() accepts. - Finally the card is associated with it's reader by the call: + Finally the card is associated with its reader by the call: VReaderStatus vreader_insert_card(VReader *vreader, VCard *vcard); diff --git a/docs/tracing.txt b/docs/tracing.txt index ea29f2c222..c541133368 100644 --- a/docs/tracing.txt +++ b/docs/tracing.txt @@ -9,7 +9,7 @@ for debugging, profiling, and observing execution. 1. Build with the 'simple' trace backend: - ./configure --trace-backend=simple + ./configure --enable-trace-backend=simple make 2. Create a file with the events you want to trace: @@ -98,12 +98,6 @@ respectively. This ensures portability between 32- and 64-bit platforms. 4. Name trace events after their function. If there are multiple trace events in one function, append a unique distinguisher at the end of the name. -5. If specific trace events are going to be called a huge number of times, this - might have a noticeable performance impact even when the trace events are - programmatically disabled. In this case you should declare the trace event - with the "disable" property, which will effectively disable it at compile - time (using the "nop" backend). - == Generic interface and monitor commands == You can programmatically query and control the dynamic state of trace events @@ -234,3 +228,43 @@ probes: --target-type system \ --target-arch x86_64 \ <trace-events >qemu.stp + +== Trace event properties == + +Each event in the "trace-events" file can be prefixed with a space-separated +list of zero or more of the following event properties. + +=== "disable" === + +If a specific trace event is going to be invoked a huge number of times, this +might have a noticeable performance impact even when the event is +programmatically disabled. + +In this case you should declare such event with the "disable" property. This +will effectively disable the event at compile time (by using the "nop" backend), +thus having no performance impact at all on regular builds (i.e., unless you +edit the "trace-events" file). + +In addition, there might be cases where relatively complex computations must be +performed to generate values that are only used as arguments for a trace +function. In these cases you can use the macro 'TRACE_${EVENT_NAME}_ENABLED' to +guard such computations and avoid its compilation when the event is disabled: + + #include "trace.h" /* needed for trace event prototype */ + + void *qemu_vmalloc(size_t size) + { + void *ptr; + size_t align = QEMU_VMALLOC_ALIGN; + + if (size < align) { + align = getpagesize(); + } + ptr = qemu_memalign(align, size); + if (TRACE_QEMU_VMALLOC_ENABLED) { /* preprocessor macro */ + void *complex; + /* some complex computations to produce the 'complex' value */ + trace_qemu_vmalloc(size, ptr, complex); + } + return ptr; + } |