Code Quality - Portability

第６章「移植性」の概要

Code Quality
http://www.amazon.co.jp/Code-Quality-~%E3%82%B3%E3%83%BC%E3%83%89%E3%83%AA%E3%83%BC%E3%83%87%E3%82%A3%E3%83%B3%E3%82%B0%E3%81%AB%E3%82%88%E3%82%8B%E9%9D%9E%E6%A9%9F%E8%83%BD%E7%89%B9%E6%80%A7%E3%81%AE%E8%AD%98%E5%88%A5%E6%8A%80%E6%B3%95~-Diomidis-Spinellis/dp/4839919798

Transcript

1. ୈ̒ষ Ҡ২ੑ Yohei Yasukawa @yasulab
2. Ҡ২ੑͷ໰୊ • ඪ४తͳ؀ڥ vs. ֵ৽తͳ؀ڥ • ҙຯͷͳ͍૪͍Λղܾ͢Δඪ४త؀ڥ • ඪ४Խཁ݅Λຬͨ͞ͳֵ͍͕৽త؀ڥ ݱ࣮ͷίʔυ͸ɼ༷ʑͳҠ২ੑʹؔ͢Δ໰୊ʹ ରॲ͠ͳ͚Ε͹ͳΒͳ͍ɽ
3. • ۩ମྫ: The application or code that can • run on both Win & Unix. • run on both Pentium & SPARC • be compiled by both Intel & GNU CC • work on both Win GUI and X Window System • be displayed both English and Japanese • work on both SCSI & SATA Ҡ২ੑͷ໰୊
4. • Q. Ͳ͏΍ͬͯղܾ͢Δ͔ʁ • A. ڞ௨ͷػೳΛந৅Խ͠ɼ ૬ҧΛখ͞ͳίʔυ෦෼ʹޮ཰తʹ੾Γ཭͢: • ໰୊ͷཁҼશମΛந৅Խ͢Δ. • ಛఆͷSW&HWʹݶఆ͢Δ. • ϓϩάϥϚʔʹରॲͯ͠΋Β͏. Ҡ২ੑͷ໰୊
7. • OS͕ҟͳΔͱ...? • ೖग़ྗͷॲཧɼจࣈͷූ߸ԽɼϑΝΠϧฤ੒ɼ Ϧιʔεͷׂ౰ํ๏, etc. .... • ͜ͷ··ͩͱࠔΔͷͰɼඪ४CϥΠϒϥϦʹ I/O(fopen/fclose)΍จࣈྻॲཧ(isdigit)͕͋Δ. 6.1. OS
8. 6.1. OS • ͱ͸͍͑ɼֵ৽తͳػೳ΋࢖͍͍ͨ. ඪ४తͳํ๏Ͱ͸࣮ݱͰ͖ͳ͍ػೳ΋͋Δ: • Web Server, DB Engine, Game, etc... for: • Thread, Lock, Devise Driver, Network. • “ඞཁͱ͞ΕΔશػೳ͕ POSIX ඪ४...!!”
9. ͔͠͠ݱ࣮͸ແৗͳͷͰ, ໧ͬͯ৚݅෇͖ίϯύΠϧ.
10. ྫ͑͹ɼPerlͷϙʔϦϯάػೳͩͱɼ͜Μͳײ͡.
11. ྫ͑͹ `./configure` ͳΒɼ͜Μͳ෩ʹߏ଄ମΛఆٛ.
12. 6.1. OS • όΠφϦϑΝΠϧ΋҆৺Ͱ͖ͳ͍: • όʔδϣϯ͕ҟͳΔͱਖ਼͘͠ಈ࡞͠ͳ͍͜ͱ΋: • syscallͷҾ਺, ߏ଄ମ, ڞ༗ϥΠϒϥϦ, etc. • e.g. PhantomJS ͸ίϯύΠϧʹ̏̌෼͔͔Δ. • → όΠφϦͰ༻ҙͪ͠Ό͑. • → OS/Arch͕ҧ͏ͱ (౰વ) “invalid hogehoge...” • ରࡦ:ޓ׵ϨΠϠͰFoo OS͕ظ଴͢Δܗࣜʹม׵.
14. 6.2. HW & Proc. Arch. • ϢʔβϓϩάϥϜ͸ (ཧ࿦্) ϓϩηοαΞʔΩς Ϋνϟͷ૬ҧʹ͸ແԑ...??? • ϝϞϦ্ͰͲͷΑ͏ʹॲཧ͞ΕΔ͔ʹؔͯࠜ͠ڌ ͷͳ͍ԾఆΛஔ͘ϓϩάϥϜ͕গͳ͘ͳ͍. • e.g. ςετͷߴ଎Խɼεϫοϓɼฏߦॲཧ. • ΋͔ͯ͠͠: ҉໧ͷԾఆΛஔ͍͍ͯΔ...?
15. 6.2. HW & Proc. Arch. ʮPDP-11Ҏ֎͸શͯ32bitͰ͋Δʯͱ͍͏҉໧ͷԾఆ
16. 6.2. HW & Proc. Arch. ʮArch. ͕ Little (or Big) Endian Ͱ͋Δʯͱ͍͏Ծఆ
17. Pt.: ҉໧ͷԾఆ͕͋Γͦ͏ͳΒɼҠ২ੑΛҙࣝ͢Δɽ 6.2. HW & Proc. Arch.
18. ඞཁ͕͋Ε͹ɼҠ২ੑΛߴΊΔίʔυΛॻ͘. 6.2. HW & Proc. Arch.
19. Ϛγϯݻ༗ͷ໋ྩ (e.g. not-and) ʹ͍ͭͯ΋ಉ͡. 6.2. HW & Proc. Arch.
20. ୈ̒ষ Ҡ২ੑ Yohei Yasukawa @yasulab