annotate target-utils/libprintf/README @ 1011:6d9b10633f10

etmsync Pirelli IMEI retrieval: fix poor use of printf() Bug reported by Vadim Yanitskiy <fixeria@osmocom.org>: the construct where a static-allocated string was passed to printf() without any format arguments causes newer compilers to report a security problem. Given that formatted output is not needed here, just fixed string output, change printf() to fputs(), and direct the error message to stderr while at it.
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 23 May 2024 17:29:57 +0000
parents e7502631a0f9
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
0
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 The present libprintf is a very light printf implementation that is well-suited
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2 for simple bare-metal programs like loadagent; in the present case it overrides
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3 the much heavier printf implementation in newlib. Programs like the present
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4 loadagent only need printf in order to scribble on the serial console port,
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5 and the most sensible implementation is to have the "character output" function
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 from the guts of printf point directly to the physical UART output routine, or
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7 a trivial wrapper that turns \n into \r\n. In contrast, newlib's version would
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 pull in the complete FILE table infrastructure and malloc etc - maybe OK for
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9 more complex embedded programs that use those facilities for other things under
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 a bona fide RTOS, but it would be disgusting to pull that stuff in for a
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11 minimal program like ours.
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 The present printf implementation has been used earlier by the same author
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14 (Michael Spacefalcon) in the StarMON family of PowerPC bootloaders, and in my
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15 MC68x302-based SDSL CPE devices (Hack-o-Rocket and OSDCU).