FreeCalypso > hg > freecalypso-tools

annotate target-utils/libc/strncmp.c @ 965:2969032bdfac

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
fcup-smsend[mult]: fix buglet in K&R C NULL pointer passing The only 100% safe way to pass a NULL pointer as a function argument in K&R C is to cast 0 to a pointer type; failing to do so may cause mysterious bugs (invalid stack frames or garbage in argument registers) on 64-bit machines. This issue has already been fixed in most of FC host tools, but I just found some missed spots: passing of NULL UDH to PDU encoding functions in fcup-smsend[mult] in the case of single (not concatenated) SMS.
author Mychaela Falconia <falcon@freecalypso.org>
date Fri, 01 Sep 2023 07:33:51 +0000
parents 7fb62fc724dc
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
87
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 /*
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2 * Compare strings (at most n bytes): s1>s2: >0 s1==s2: 0 s1<s2: <0
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3 */
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5 strncmp(s1, s2, n)
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 register char *s1, *s2;
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7 register n;
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 {
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9 while (--n >= 0 && *s1 == *s2++)
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 if (*s1++ == '\0')
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11 return(0);
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12 return(n<0 ? 0 : *s1 - *--s2);
7fb62fc724dc target-utils/libc: beginning of newlib-ectomy
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 }