since emergstream always call syslog_force, but syslog_force is designed
for the interrupt context, and then doesn't mean any emergency thing.
On the other hand, emergstream has other bad side effect:
1.Can't output to file or dev channel
2.Can't work well with the interrupt buffer
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Author: Gregory Nutt <gnutt@nuttx.org>
TODO: Remove 'Missing fscanf()' bug
Clean up remaining complaints for tools/nxstyle
Apply tools/detab, rmcr, convert-comments, lowhex, and indent.sh to the new and highly modified files.
Author: Johannes <nivus.entwicklung@gmail.com>
- Move vscanf logic to lib_sscanf.c Switched to stream interface (tricky, because the old implementation used massive read ahead, which isn't suitable for streams, chars already read are gone).
- Added scanf and fscanf
- Added hh, h, and ll modifiers
- Fixes for standard compliance in scanf
- Fixes for standard compliance in strto... function family (don't consume single '-' or '+', allow sign in strotul(l))
This was an interesting exercise to see just how small you could get NuttX, but otherwise it was not useful: (1) the NSH code violated the OS interface layer by callup up_getc and up_putc directly, and (2) while waiting for character input, NSH would call up_getc() which would hog all of the CPU. NOt a reasonably solution other than as a proof of concept.
Atmel toolchain AVR compiler provides a transparent in-flash object support using __flash and __memx symbols. The former indicates to compiler that this is a flash-based object. The later used with pointer indicates that the referenced object may reside either in flash or in RAM. The compiler automatically makes 32-bit pointer with flag indicating whether referenced object is in flash or RAM and generates code to access either in run-time. Thus, any function that accepts __memx object can transparently work with RAM and flash objects.
For platforms with a Harvard architecture and a very small RAM like AVR this allows to move all constant strings used in trace messages to flash in the instruction address space, releasing resources for other things.
This change introduces IOBJ and IPTR type qualifiers. The 'I' indicates that the object may like in instruction space on a Harvard architecture machine.
For platforms that do not have __flash and __memx or similar symbols IOBJ and IPTR are empty, making the types equivalent to, for example, 'const char' and 'const char*'. For Atmel compiler these will become 'const __flash char' and 'const __memx char*'. All printf() functions and syslog() functions are changed so that the qualifier is used with the format parameter.
From: Dimitry Kloper <dikloper@cisco.com>
