uproctrace

factor reading file to seprate file
Parent d56e99d
Stefan Schuermans

Stefan Schuermans commited on 2020-05-17 19:05:35
Showing 4 changed files, with 75 additions and 57 deletions.

liblwptev/CMakeLists.txt
View file @ 4199392
... ... 
@@ -22,6 +22,8 @@ add_library(
22 22 
   src/macros.h
23 23 
   src/proc_begin.c
24 24 
   src/proc_end.c
25 
+  src/read_file.c
26 
+  src/read_file.h
25 27 
   src/stringlist.c
26 28 
   src/stringlist.h
27 29 
   src/symlink.c
liblwptev/src/read_file.c
View file @ 4199392
... ... 
@@ -0,0 +1,59 @@
1 
+#include "stringlist.h"
2 
+#include "cleaner.h"
3 
+
4 
+#include <fcntl.h>
5 
+#include <stdlib.h>
6 
+#include <string.h>
7 
+#include <sys/types.h>
8 
+#include <sys/stat.h>
9 
+#include <unistd.h>
10 
+
11 
+char * lwptev_read_file(char const *pathname, size_t *size) {
12 
+  /* it is not possible to get file size before, because this yields zero for
13 
+     files like /proc/self/cmdline */
14 
+  *size = 0;
15 
+  /* open file */
16 
+  int fd = open(pathname, O_RDONLY);
17 
+  if (fd == -1) {
18 
+    return NULL;
19 
+  }
20 
+  /* get initial buffer */
21 
+  size_t sz = 4096;
22 
+  char *data = malloc(sz);
23 
+  if (! data) {
24 
+    close(fd);
25 
+    return NULL;
26 
+  }
27 
+  /* read file contents - potentially iteratively */
28 
+  size_t pos = 0;
29 
+  while (1) {
30 
+    /* read file contents */
31 
+    ssize_t len = read(fd, data + pos, sz - pos);
32 
+    /* error -> cleanup and return failure */
33 
+    if (len < 0) {
34 
+      free(data);
35 
+      close(fd);
36 
+      return NULL;
37 
+    }
38 
+    if (len == 0 ) {
39 
+      /* end of file -> return data */
40 
+      *size = pos;
41 
+      return data;
42 
+    }
43 
+    /* data read -> add to buffer */
44 
+    pos += len;
45 
+    /* buffer full ? -> enlarge */
46 
+    if (pos >= sz) {
47 
+      sz *= 2;
48 
+      char *data2 = realloc(data, sz);
49 
+      /* out of memory ? -> cleanup and return failure */
50 
+      if (! data2) {
51 
+        free(data);
52 
+        close(fd);
53 
+        return NULL;
54 
+      }
55 
+      /* use new buffer */
56 
+      data = data2;
57 
+    }
58 
+  }
59 
+}
liblwptev/src/read_file.h
View file @ 4199392
... ... 
@@ -0,0 +1,12 @@
1 
+#ifndef LWPTEV_READ_FILE_H
2 
+#define LWPTEV_READ_FILE_H
3 
+
4 
+/**
5 
+ * @brief read file contents
6 
+ * @param[in] pathname path to file containing zero-terminated string list
7 
+ * @param[out] *size size of file contents
8 
+ * @return pointer to malloc-ed file contents or NULL
9 
+ */
10 
+char * lwptev_read_file(char const *pathname, size_t *size);
11 
+
12 
+#endif /* #ifndef LWPTEV_READ_FILE_H */
liblwptev/src/stringlist.c
View file @ 4199392
... ... 
@@ -1,5 +1,6 @@
1 1 
 #include "stringlist.h"
2 2 
 #include "cleaner.h"
3 
+#include "read_file.h"
3 4
4 5 
 #include <fcntl.h>
5 6 
 #include <stdlib.h>
... ... 
@@ -8,62 +9,6 @@
8 9 
 #include <sys/stat.h>
9 10 
 #include <unistd.h>
10 11
11 
-/**
12 
- * @brief read file contents
13 
- * @param[in] pathname path to file containing zero-terminated string list
14 
- * @param[out] *size size of file contents
15 
- * @return pointer to malloc-ed file contents or NULL
16 
- */
17 
-static char * lwptev_stringlist_read_file(char const *pathname, size_t *size) {
18 
-  /* it is not possible to get file size before, because this yields zero for
19 
-     files like /proc/self/cmdline */
20 
-  *size = 0;
21 
-  /* open file */
22 
-  int fd = open(pathname, O_RDONLY);
23 
-  if (fd == -1) {
24 
-    return NULL;
25 
-  }
26 
-  /* get initial buffer */
27 
-  size_t sz = 4096;
28 
-  char *data = malloc(sz);
29 
-  if (! data) {
30 
-    close(fd);
31 
-    return NULL;
32 
-  }
33 
-  /* read file contents - potentially iteratively */
34 
-  size_t pos = 0;
35 
-  while (1) {
36 
-    /* read file contents */
37 
-    ssize_t len = read(fd, data + pos, sz - pos);
38 
-    /* error -> cleanup and return failure */
39 
-    if (len < 0) {
40 
-      free(data);
41 
-      close(fd);
42 
-      return NULL;
43 
-    }
44 
-    if (len == 0 ) {
45 
-      /* end of file -> return data */
46 
-      *size = pos;
47 
-      return data;
48 
-    }
49 
-    /* data read -> add to buffer */
50 
-    pos += len;
51 
-    /* buffer full ? -> enlarge */
52 
-    if (pos >= sz) {
53 
-      sz *= 2;
54 
-      char *data2 = realloc(data, sz);
55 
-      /* out of memory ? -> cleanup and return failure */
56 
-      if (! data2) {
57 
-        free(data);
58 
-        close(fd);
59 
-        return NULL;
60 
-      }
61 
-      /* use new buffer */
62 
-      data = data2;
63 
-    }
64 
-  }
65 
-}
66 
-
67 12 
 /**
68 13 
  * @brief make array with pointers to strings
69 14 
  * @param[in] data pointer to string list
... ... 
@@ -101,7 +46,7 @@ int lwptev_stringlist_read(char const *pathname, size_t *n, char ***strs,
101 46 
   *strs = NULL;
102 47 
   /* read file contents */
103 48 
   size_t sz;
104 
-  char *data = lwptev_stringlist_read_file(pathname, &sz);
49 
+  char *data = lwptev_read_file(pathname, &sz);
105 50 
   if (! data) {
106 51 
     lwptev_cleaner_cleanup(cleaner);
107 52 
     return -1;
108 53