linux下库的使用--静态库
一、编辑代码如下：
#vector.h 1 #ifndef vector_h 2 #define vector_h 3 4 void addVec(int *xP, int *yP, int *zP, int Num); 5 void mulVec(int *xP, int *yP, int *zP, int Num); 6 7 #endif #addVec.c 1 #include "vector.h" 2 3 void addVec(int *xP, int *yP, int *zP, int Num){ 4 for(int i = 0; i < n; i++){ 5 zP[i] = xP[i] + yP[i]; 6 } 7 8 return; 9 } ~ #mulVec.c 1 #include "vector.h" 2 3 void mulVec(int *xP, int *yP, int *zP, int Num){ 4 for(int i = 0; i < n; i++){ 5 zP[i] = xP[i] * yP[i]; 6 } 7 8 return; 9 } #testVec.c 1 #include <stdio.h> 2 #include "vector.h" 3 4 int x[2] = {1, 2}; 5 int y[2] = {3, 4}; 6 int z[2]; 7 8 int main(int argc, char **argv) 9 { 10 addVec(x, y, z, 2); 11 printf("z = [%d %d]\n", z[0], z[1]); 12 13 return 0; 14 }
二、生成静态库文件：
1、gcc -Og -c *Vec.c //生成目标文件
2、ls *.o 或 ls | grep .o //查看目标文件
3、ar crs libVector.a addVec.o mulVec.o //生成静态库文件
4、ls *.a //查看生成的库文件
5、file libVector.a //查看文件类型
6、ar -t libVector.a //查看文件内容
三、使用静态库文件：
gcc testVec.o libVector.a -o testVec //生成可执行文件
四、运行程序：
testVec //运行，出结果z = [4 6]
五、查看testVec代码
objdump -d testVec,结果：
objdump -d testVec testVec： 文件格式 elf64-x86-64 Disassembly of section .init: 0000000000001000 <_init>: 1000: f3 0f 1e fa endbr64 1004: 48 83 ec 08 sub $0x8,%rsp 1008: 48 8b 05 d9 2f 00 00 mov 0x2fd9(%rip),%rax # 3fe8 <__gmon_start__> 100f: 48 85 c0 test %rax,%rax 1012: 74 02 je 1016 <_init+0x16> 1014: ff d0 callq *%rax 1016: 48 83 c4 08 add $0x8,%rsp 101a: c3 retq Disassembly of section .plt: 0000000000001020 <.plt>: 1020: ff 35 e2 2f 00 00 pushq 0x2fe2(%rip) # 4008 <_GLOBAL_OFFSET_TABLE_+0x8> 1026: ff 25 e4 2f 00 00 jmpq *0x2fe4(%rip) # 4010 <_GLOBAL_OFFSET_TABLE_+0x10> 102c: 0f 1f 40 00 nopl 0x0(%rax) 0000000000001030 <printf@plt>: 1030: ff 25 e2 2f 00 00 jmpq *0x2fe2(%rip) # 4018 <printf@GLIBC_2.2.5> 1036: 68 00 00 00 00 pushq $0x0 103b: e9 e0 ff ff ff jmpq 1020 <.plt> Disassembly of section .text: 0000000000001040 <_start>: 1040: f3 0f 1e fa endbr64 1044: 31 ed xor %ebp,%ebp 1046: 49 89 d1 mov %rdx,%r9 1049: 5e pop %rsi 104a: 48 89 e2 mov %rsp,%rdx 104d: 48 83 e4 f0 and $0xfffffffffffffff0,%rsp 1051: 50 push %rax 1052: 54 push %rsp 1053: 4c 8d 05 c6 01 00 00 lea 0x1c6(%rip),%r8 # 1220 <__libc_csu_fini> 105a: 48 8d 0d 4f 01 00 00 lea 0x14f(%rip),%rcx # 11b0 <__libc_csu_init> 1061: 48 8d 3d d1 00 00 00 lea 0xd1(%rip),%rdi # 1139 <main> 1068: ff 15 72 2f 00 00 callq *0x2f72(%rip) # 3fe0 <__libc_start_main@GLIBC_2.2.5> 106e: f4 hlt 106f: 90 nop 0000000000001070 <deregister_tm_clones>: 1070: 48 8d 3d c9 2f 00 00 lea 0x2fc9(%rip),%rdi # 4040 <__TMC_END__> 1077: 48 8d 05 c2 2f 00 00 lea 0x2fc2(%rip),%rax # 4040 <__TMC_END__> 107e: 48 39 f8 cmp %rdi,%rax 1081: 74 15 je 1098 <deregister_tm_clones+0x28> 1083: 48 8b 05 4e 2f 00 00 mov 0x2f4e(%rip),%rax # 3fd8 <_ITM_deregisterTMCloneTable> 108a: 48 85 c0 test %rax,%rax 108d: 74 09 je 1098 <deregister_tm_clones+0x28> 108f: ff e0 jmpq *%rax 1091: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 1098: c3 retq 1099: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 00000000000010a0 <register_tm_clones>: 10a0: 48 8d 3d 99 2f 00 00 lea 0x2f99(%rip),%rdi # 4040 <__TMC_END__> 10a7: 48 8d 35 92 2f 00 00 lea 0x2f92(%rip),%rsi # 4040 <__TMC_END__> 10ae: 48 29 fe sub %rdi,%rsi 10b1: 48 89 f0 mov %rsi,%rax 10b4: 48 c1 ee 3f shr $0x3f,%rsi 10b8: 48 c1 f8 03 sar $0x3,%rax 10bc: 48 01 c6 add %rax,%rsi 10bf: 48 d1 fe sar %rsi 10c2: 74 14 je 10d8 <register_tm_clones+0x38> 10c4: 48 8b 05 25 2f 00 00 mov 0x2f25(%rip),%rax # 3ff0 <_ITM_registerTMCloneTable> 10cb: 48 85 c0 test %rax,%rax 10ce: 74 08 je 10d8 <register_tm_clones+0x38> 10d0: ff e0 jmpq *%rax 10d2: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 10d8: c3 retq 10d9: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 00000000000010e0 <__do_global_dtors_aux>: 10e0: f3 0f 1e fa endbr64 10e4: 80 3d 55 2f 00 00 00 cmpb $0x0,0x2f55(%rip) # 4040 <__TMC_END__> 10eb: 75 33 jne 1120 <__do_global_dtors_aux+0x40> 10ed: 55 push %rbp 10ee: 48 83 3d 02 2f 00 00 cmpq $0x0,0x2f02(%rip) # 3ff8 <__cxa_finalize@GLIBC_2.2.5> 10f5: 00 10f6: 48 89 e5 mov %rsp,%rbp 10f9: 74 0d je 1108 <__do_global_dtors_aux+0x28> 10fb: 48 8b 3d 26 2f 00 00 mov 0x2f26(%rip),%rdi # 4028 <__dso_handle> 1102: ff 15 f0 2e 00 00 callq *0x2ef0(%rip) # 3ff8 <__cxa_finalize@GLIBC_2.2.5> 1108: e8 63 ff ff ff callq 1070 <deregister_tm_clones> 110d: c6 05 2c 2f 00 00 01 movb $0x1,0x2f2c(%rip) # 4040 <__TMC_END__> 1114: 5d pop %rbp 1115: c3 retq 1116: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1) 111d: 00 00 00 1120: c3 retq 1121: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1) 1128: 00 00 00 00 112c: 0f 1f 40 00 nopl 0x0(%rax) 0000000000001130 <frame_dummy>: 1130: f3 0f 1e fa endbr64 1134: e9 67 ff ff ff jmpq 10a0 <register_tm_clones> 0000000000001139 <main>: 1139: 48 83 ec 08 sub $0x8,%rsp 113d: b9 02 00 00 00 mov $0x2,%ecx 1142: 48 8d 15 ff 2e 00 00 lea 0x2eff(%rip),%rdx # 4048 <z> 1149: 48 8d 35 e0 2e 00 00 lea 0x2ee0(%rip),%rsi # 4030 <y> 1150: 48 8d 3d e1 2e 00 00 lea 0x2ee1(%rip),%rdi # 4038 <x> 1157: e8 27 00 00 00 callq 1183 <addVec> 115c: 8b 15 ea 2e 00 00 mov 0x2eea(%rip),%edx # 404c <z+0x4> 1162: 8b 35 e0 2e 00 00 mov 0x2ee0(%rip),%esi # 4048 <z> 1168: 48 8d 3d 95 0e 00 00 lea 0xe95(%rip),%rdi # 2004 <_IO_stdin_used+0x4> 116f: b8 00 00 00 00 mov $0x0,%eax 1174: e8 b7 fe ff ff callq 1030 <printf@plt> 1179: b8 00 00 00 00 mov $0x0,%eax 117e: 48 83 c4 08 add $0x8,%rsp 1182: c3 retq 0000000000001183 <addVec>: 1183: 49 89 f9 mov %rdi,%r9 1186: 49 89 f0 mov %rsi,%r8 1189: 48 89 d7 mov %rdx,%rdi 118c: 89 ce mov %ecx,%esi 118e: b8 00 00 00 00 mov $0x0,%eax 1193: eb 11 jmp 11a6 <addVec+0x23> 1195: 48 63 d0 movslq %eax,%rdx 1198: 41 8b 0c 90 mov (%r8,%rdx,4),%ecx 119c: 41 03 0c 91 add (%r9,%rdx,4),%ecx 11a0: 89 0c 97 mov %ecx,(%rdi,%rdx,4) 11a3: 83 c0 01 add $0x1,%eax 11a6: 39 f0 cmp %esi,%eax 11a8: 7c eb jl 1195 <addVec+0x12> 11aa: c3 retq 11ab: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 00000000000011b0 <__libc_csu_init>: 11b0: f3 0f 1e fa endbr64 11b4: 41 57 push %r15 11b6: 4c 8d 3d 2b 2c 00 00 lea 0x2c2b(%rip),%r15 # 3de8 <__frame_dummy_init_array_entry> 11bd: 41 56 push %r14 11bf: 49 89 d6 mov %rdx,%r14 11c2: 41 55 push %r13 11c4: 49 89 f5 mov %rsi,%r13 11c7: 41 54 push %r12 11c9: 41 89 fc mov %edi,%r12d 11cc: 55 push %rbp 11cd: 48 8d 2d 1c 2c 00 00 lea 0x2c1c(%rip),%rbp # 3df0 <__do_global_dtors_aux_fini_array_entry> 11d4: 53 push %rbx 11d5: 4c 29 fd sub %r15,%rbp 11d8: 48 83 ec 08 sub $0x8,%rsp 11dc: e8 1f fe ff ff callq 1000 <_init> 11e1: 48 c1 fd 03 sar $0x3,%rbp 11e5: 74 1f je 1206 <__libc_csu_init+0x56> 11e7: 31 db xor %ebx,%ebx 11e9: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 11f0: 4c 89 f2 mov %r14,%rdx 11f3: 4c 89 ee mov %r13,%rsi 11f6: 44 89 e7 mov %r12d,%edi 11f9: 41 ff 14 df callq *(%r15,%rbx,8) 11fd: 48 83 c3 01 add $0x1,%rbx 1201: 48 39 dd cmp %rbx,%rbp 1204: 75 ea jne 11f0 <__libc_csu_init+0x40> 1206: 48 83 c4 08 add $0x8,%rsp 120a: 5b pop %rbx 120b: 5d pop %rbp 120c: 41 5c pop %r12 120e: 41 5d pop %r13 1210: 41 5e pop %r14 1212: 41 5f pop %r15 1214: c3 retq 1215: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1) 121c: 00 00 00 00 0000000000001220 <__libc_csu_fini>: 1220: f3 0f 1e fa endbr64 1224: c3 retq Disassembly of section .fini: 0000000000001228 <_fini>: 1228: f3 0f 1e fa endbr64 122c: 48 83 ec 08 sub $0x8,%rsp 1230: 48 83 c4 08 add $0x8,%rsp 1234: c3 retq
objdump -d addVec.o结果：
0000000000000000 <addVec>: 0: 49 89 f9 mov %rdi,%r9 3: 49 89 f0 mov %rsi,%r8 6: 48 89 d7 mov %rdx,%rdi 9: 89 ce mov %ecx,%esi b: b8 00 00 00 00 mov $0x0,%eax 10: eb 11 jmp 23 <addVec+0x23> 12: 48 63 d0 movslq %eax,%rdx 15: 41 8b 0c 90 mov (%r8,%rdx,4),%ecx 19: 41 03 0c 91 add (%r9,%rdx,4),%ecx 1d: 89 0c 97 mov %ecx,(%rdi,%rdx,4) 20: 83 c0 01 add $0x1,%eax 23: 39 f0 cmp %esi,%eax 25: 7c eb jl 12 <addVec+0x12> 27: c3 retq
发现addVec.o全部进入了可执行文件中，而mulVec.o则没有进入，唯一的区别就是在地址上的不同。
静态库使用中，必须将用到的所有的目标文件加进最后形成的可执行文件中，会造成文件过大的情况出现。
人就像是被蒙着眼推磨的驴子，生活就像一条鞭子；当鞭子抽到你背上时，你就只能一直往前走，虽然连你也不知道要走到什么时候为止，便一直这么坚持着。
