generic-library/bionic
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Bug 3330205 Thread safety for bignum powers of 5

Browse Source 
Change-Id: I739a06f9037a9fb643276f61601f0f3e192581b8
This commit is contained in:
Glenn Kasten
2011-01-09 09:50:10 -08:00
parent 015610e64e
commit 144a5d3c86
1 changed files with 5 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
libc/stdlib/strtod.c
View File

@@ -754,6 +754,7 @@ mult
} }
static Bigint *p5s; static Bigint *p5s;
static pthread_mutex_t p5s_mutex = PTHREAD_MUTEX_INITIALIZER;
static Bigint * static Bigint *
pow5mult pow5mult
@@ -775,11 +776,13 @@ pow5mult
if (!(k = (unsigned int) k >> 2)) if (!(k = (unsigned int) k >> 2))
return b; return b;
mutex_lock(&p5s_mutex);
if (!(p5 = p5s)) { if (!(p5 = p5s)) {
/* first time */ /* first time */
p5 = i2b(625); p5 = i2b(625);
if (p5 == BIGINT_INVALID) { if (p5 == BIGINT_INVALID) {
Bfree(b); Bfree(b);
mutex_unlock(&p5s_mutex);
return p5; return p5;
} }
p5s = p5; p5s = p5;
@@ -797,6 +800,7 @@ pow5mult
p51 = mult(p5,p5); p51 = mult(p5,p5);
if (p51 == BIGINT_INVALID) { if (p51 == BIGINT_INVALID) {
Bfree(b); Bfree(b);
mutex_unlock(&p5s_mutex);
return p51; return p51;
} }
p5->next = p51; p5->next = p51;
@@ -804,6 +808,7 @@ pow5mult
} }
p5 = p51; p5 = p51;
} }
mutex_unlock(&p5s_mutex);
return b; return b;
} }