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

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
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Mychaela Falconia <falcon@freecalypso.org>
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1 The present libprintf is a very light printf implementation that is well-suited
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Mychaela Falconia <falcon@freecalypso.org>
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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>
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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>
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4 loadagent only need printf in order to scribble on the serial console port,
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Mychaela Falconia <falcon@freecalypso.org>
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5 and the most sensible implementation is to have the "character output" function
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Mychaela Falconia <falcon@freecalypso.org>
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6 from the guts of printf point directly to the physical UART output routine, or
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Mychaela Falconia <falcon@freecalypso.org>
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7 a trivial wrapper that turns \n into \r\n. In contrast, newlib's version would
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Mychaela Falconia <falcon@freecalypso.org>
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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>
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9 more complex embedded programs that use those facilities for other things under
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Mychaela Falconia <falcon@freecalypso.org>
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10 a bona fide RTOS, but it would be disgusting to pull that stuff in for a
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Mychaela Falconia <falcon@freecalypso.org>
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11 minimal program like ours.
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13 The present printf implementation has been used earlier by the same author
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Mychaela Falconia <falcon@freecalypso.org>
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14 (Michael Spacefalcon) in the StarMON family of PowerPC bootloaders, and in my
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15 MC68x302-based SDSL CPE devices (Hack-o-Rocket and OSDCU).