Annotation of libwww/Library/src/HTChunk.html, revision 2.26
2.8 timbl 1: <HTML>
2: <HEAD>
2.26 ! frystyk 3: <TITLE>W3C Reference Library libwww Dynamic Array Class</TITLE>
2.24 frystyk 4: <!-- Changed by: Henrik Frystyk Nielsen, 5-Feb-1996 -->
2.11 frystyk 5: </HEAD>
2.6 timbl 6: <BODY>
2.11 frystyk 7:
2.18 frystyk 8: <H1>Dynamic Array Class</H1>
2.10 frystyk 9:
2.11 frystyk 10: <PRE>
11: /*
2.16 frystyk 12: ** (c) COPYRIGHT MIT 1995.
2.11 frystyk 13: ** Please first read the full copyright statement in the file COPYRIGH.
14: */
15: </PRE>
16:
2.14 frystyk 17: This module implements a flexible array. It is a general utility
18: module. A chunk is a structure which may be extended. These routines
19: create and append data to chunks, automatically reallocating them as
20: necessary. It is garanteed that the array is <B>'\0'</B> terminated
21: at all times, so the terminating function, <A
22: HREF="HTChunk.html#Terminate">HTChunkTerminate</A> is only necessary
23: to adjust the size in the chunk structure (the <B>'\0'</B> counts as a
24: character when counting the size of the chunk. <P>
2.10 frystyk 25:
2.11 frystyk 26: This module is implemented by <A HREF="HTChunk.c">HTChunk.c</A>, and
2.20 frystyk 27: it is a part of the <A HREF="http://www.w3.org/pub/WWW/Library/"> W3C
2.23 frystyk 28: Reference Library</A>. <P>
29:
30: <IMG SRC="../../Icons/32x32/caution.gif" ALT="NOTE"> The names
31: without a "_" (made as a <CODE>#define</CODE>'s) are only provided for
32: backwards compatibility and should not be used.
2.10 frystyk 33:
34: <PRE>
35: #ifndef HTCHUNK_H
2.9 frystyk 36: #define HTCHUNK_H
2.12 roeber 37:
2.9 frystyk 38: </PRE>
39:
2.18 frystyk 40: <H2>Private Data Structure</H2>
41:
2.23 frystyk 42: This structure should not be referenced outside this module!
2.18 frystyk 43:
44: <PRE>
45: typedef struct {
2.1 timbl 46: int size; /* In bytes */
47: int growby; /* Allocation unit in bytes */
48: int allocated; /* Current size of *data */
49: char * data; /* Pointer to malloced area or 0 */
50: } HTChunk;
2.18 frystyk 51: </PRE>
2.1 timbl 52:
2.6 timbl 53: <H2>Create new chunk</H2>
2.18 frystyk 54:
55: Create a new chunk and specify the number of bytes to allocate at a
56: time when the chunk is later extended. Arbitrary but normally a
57: trade-off time vs. memory
2.6 timbl 58:
59: <PRE>
2.22 frystyk 60: #define HTChunkCreate(growby) HTChunk_new(growby)
61: extern HTChunk * HTChunk_new (int growby);
2.18 frystyk 62: </PRE>
2.1 timbl 63:
2.18 frystyk 64: <H2>Free a chunk</H2>
2.1 timbl 65:
2.18 frystyk 66: Free a chunk created by <CODE>HTChunkCreate</CODE>from memory
2.6 timbl 67:
68: <PRE>
2.22 frystyk 69: #define HTChunkFree(ch) HTChunk_delete(ch)
70: extern void HTChunk_delete (HTChunk * ch);
2.18 frystyk 71: </PRE>
2.1 timbl 72:
2.18 frystyk 73: <H2>Clear a chunk</H2>
2.1 timbl 74:
2.18 frystyk 75: Keep the chunk in memory but clear all data kept inside.
2.6 timbl 76:
77: <PRE>
2.22 frystyk 78: #define HTChunkClear(ch) HTChunk_clear(ch)
79: extern void HTChunk_clear (HTChunk * ch);
2.18 frystyk 80: </PRE>
2.1 timbl 81:
2.18 frystyk 82: <H2>Ensure a chunk has a certain space in</H2>
2.1 timbl 83:
2.18 frystyk 84: Make sure that a chunk has a certain size. If this is not the case
85: then the chunk is expanded. Nothing is done if the current size if
86: bigger than the size requested.
2.6 timbl 87:
88: <PRE>
2.22 frystyk 89: #define HTChunkEnsure(ch, s) HTChunk_ensure(ch, s)
90: extern void HTChunk_ensure (HTChunk * ch, int s);
2.18 frystyk 91: </PRE>
2.1 timbl 92:
2.18 frystyk 93: <H2>Append a character to a chunk</H2>
2.1 timbl 94:
2.18 frystyk 95: Add the character and increment the size of the chunk by one character
96:
97: <PRE>
2.22 frystyk 98: #define HTChunkPutc(ch, c) HTChunk_putc(ch, c)
99: extern void HTChunk_putc (HTChunk * ch, char c);
2.6 timbl 100: </PRE>
2.1 timbl 101:
2.18 frystyk 102: <H2>Append a string to a chunk</H2>
103:
104: Add the string and increment the size of the chunk by the length of
105: the string (without the trailing zero)
2.1 timbl 106:
2.18 frystyk 107: <PRE>
2.22 frystyk 108: #define HTChunkPuts(ch, str) HTChunk_puts(ch, str)
2.25 frystyk 109: extern void HTChunk_puts (HTChunk * ch, const char *str);
2.22 frystyk 110: </PRE>
111:
112: <H2>Append a block to a chunk</H2>
113:
114: Add the block and increment the size of the chunk by the len
115:
116: <PRE>
2.25 frystyk 117: extern void HTChunk_putb (HTChunk * ch, const char *block, int len);
2.6 timbl 118: </PRE>
2.18 frystyk 119:
120: <A NAME="Terminate"><H2>Zero Terminate a chunk</H2></A>
121:
122: As a chunk often is a dynamic string, it needs to be terminated by a
123: zero in order to be used in C. However, <B>by default</B> any chunk
124: <EM>is</EM> always zero terminated, so the only purpose of this
125: function is to increment the size counter with one corresponding to
126: the zero.
2.6 timbl 127:
128: <PRE>
2.24 frystyk 129: #define HTChunkTerminate(ch) HTChunk_terminate(ch)
130: #define HTChunk_terminate(ch) HTChunk_putc((ch), '\0')
2.18 frystyk 131: </PRE>
2.1 timbl 132:
2.18 frystyk 133: <H2>Return Pointer to Data</H2>
2.1 timbl 134:
2.18 frystyk 135: This define converts a chunk to a normal char pointer so that it can
136: be parsed to any ANSI C string function.
2.1 timbl 137:
2.18 frystyk 138: <PRE>
2.22 frystyk 139: #define HTChunkData(me) ((me) ? (me)->data : NULL)
140: #define HTChunk_data(me) ((me) ? (me)->data : NULL)
2.6 timbl 141: </PRE>
2.18 frystyk 142:
143: <H2>Return Current Size</H2>
144:
145: Returns the current size of the chunk
146:
2.6 timbl 147: <PRE>
2.22 frystyk 148: #define HTChunkSize(me) ((me) ? (me)->size : -1)
149: #define HTChunk_size(me) ((me) ? (me)->size : -1)
2.6 timbl 150: </PRE>
151:
152: <PRE>
2.18 frystyk 153: #endif
154: </PRE>
2.1 timbl 155:
2.18 frystyk 156: End of Declaration
2.6 timbl 157:
2.18 frystyk 158: </BODY>
2.8 timbl 159: </HTML>
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